Rule 8.3 - RIO TINTO PLC

FORM 8.3

    DEALINGS BY PERSONS WITH INTERESTS IN SECURITIES REPRESENTING 1% OR MORE
              (Rule 8.3 of the City Code on Takeovers and Mergers)


1.   KEY INFORMATION

Name of person dealing        BARCLAYS PLC
(Note 1)
Company dealt in              RIO TINTO
Class of relevant security    ORD GBP0.10
to which the dealings being
disclosed relate (Note 2)
Date of dealing               20 December 2007

2.   INTERESTS, SHORT POSITIONS AND RIGHTS TO SUBSCRIBE

(a)  Interests and short positions (following dealing) in the class of relevant
security dealt in (Note 3)

                            Long                     Short

                      Number       (%)         Number       (%)

(1) Relevant      48,322,378      4.85%    2,131,360       0.21%
securities
(2) Derivatives    2,342,862      0.23%      166,069       0.02%
(other than
options)
(3) Options and      204,131      0.02%    1,303,531       0.13%
agreements to
purchase/sell
Total             50,869,096      5.10%    3,600,960       0.36%


(b)  Interests and short positions in relevant securities of the company, other
     than the class dealt in (Note 3)

Class of                    Long                     Short
relevant
security:

                  Number              (%)   Number              (%)

(1) Relevant
securities

(2) Derivatives
(other than
options)

(3) Options and
agreements to
purchase/sell

Total


  (c)  Rights to subscribe (Note 3)

Class of relevant security:   Details



3.   DEALINGS (Note 4)

  (a)  Purchases and sales

Purchase/sale Number of Securities Price per unit
                                   (GBP)
Purchase      1,098                50.9571
Purchase      931                  50.9426
Purchase      1,717                51.3000
Purchase      5,610                51.3085
Purchase      282                  50.9971
Purchase      3,188                51.3000
Purchase      81,034               50.9388
Purchase      79,000               50.9300
Purchase      1,075,714            50.5800
Purchase      32,779               51.0949
Purchase      7,406                50.9872
Purchase      282                  51.1500
Purchase      113,750              50.7000
Purchase      1,842                50.7727
Purchase      30,211               50.8542
Purchase      132,924              50.9890
Purchase      26,000               51.1613
Purchase      380,769              51.0200
Purchase      88,975               50.9557
Purchase      33,748               51.0165
Purchase      11,100               50.5683
Purchase      32,779               51.0949
Purchase      104                  51.1206
Purchase      1,752                51.3000
Purchase      1,911                50.9788
Purchase      2,576                51.0826
Purchase      10,615               50.7500
Purchase      962                  51.3000
Purchase      4,006                50.9092
Sale          50                   50.8348
Sale          1,098                50.9571
Sale          120                  51.0275
Sale          28                   Transfer
Sale          931                  50.9375
Sale          12                   51.0350
Sale          350                  51.2725
Sale          65                   51.3451
Sale          132,924              50.9890
Sale          4,006                50.9000
Sale          2,206                51.3000
Sale          50                   51.0926
Sale          7,406                50.9872
Sale          32,779               51.0949
Sale          70                   50.9950
Sale          26,000               51.1537
Sale          5,610                51.2992
Sale          1,842                50.7682
Sale          282                  50.9971
Sale          1,097                51.3000
Sale          1,075,714            50.5800
Sale          55                   50.1275
Sale          7,406                50.9872
Sale          132,924              50.9890
Sale          11,100               50.5683
Sale          306                  50.8500
Sale          1,752                51.3000
Sale          79,000               50.9300
Sale          1,000                51.0000
Sale          70                   50.6425
Sale          155                  50.9400
Sale          130                  51.3232
Sale          11,100               50.5683
Sale          1,098                50.9571
Sale          10,615               50.7500
Sale          3,788                51.3000
Sale          33,748               51.0165
Sale          608                  50.8500
Sale          104                  51.1129
Sale          30,211               50.8542
Sale          40                   50.9820
Sale          88,975               50.9557
Sale          1,911                50.9742
Sale          282                  51.1500
Sale          2,576                51.0775

(b)  Derivatives transactions (other than options)
Product name,  Long/Short    Number of     Price per
(e.g. CFD)     (Note 6)      Securities    unit (GBP)
CFD            Short         1842          50.7727
CFD            Short         4006          50.9091
CFD            Short         931           50.9425
CFD            Short         26000         51.1613
CFD            Long          88975         50.9557
CFD            Long          1098          50.9571
CFD            Long          1911          50.9741
CFD            Long          7406          50.9871
CFD            Long          33748         51.0165
CFD            Long          2576          51.0775
CFD            Long          104           51.1128
CFD            Long          5610          51.2992


(c)  Options transactions in respect of existing securities

(i)  Writing, selling, purchasing or varying

Product name,   Writing,          Number of          Exercise  Type, e.g.      Expiry      Option money
e.g. call       selling,          securities to      price     American,       date        paid/received
option          purchasing,       which the option             European etc.               per unit (GBP)
                varying etc.      relates (GBP)
CALL            Selling           175                50        EURO            21/12/2007  .92
CALL            Selling           2                  50        EURO            21/12/2007  1.01
CALL            Selling           8                  50        EURO            21/12/2007  1.11
CALL            Selling           90                 50        EURO            21/12/2007  1.13


(ii) Exercising

Product name, e.g.  Number of           Exercise price per
call option         securities          unit (Note 5)




(d)  Other dealings (including new securities) (Note 4)


Nature of transaction Details           Price per unit
(Note 8)                                (if applicable)
                                        (Note 5)




4.   OTHER INFORMATION
None

Agreements, arrangements or understandings relating to options or derivatives


Full details of any agreement, arrangement or understanding between the
person disclosing and any other person relating to the voting rights of
any relevant securities under any option referred to on this form or
relating to the voting rights or future acquisition or disposal of any
relevant securities to which any derivative referred to on this form is
referenced.  If none, this should be stated.




Is a Supplemental Form 8 attached? (Note 9)                 YES


Date of disclosure                         21 December 2007
Contact name                               Geoff Smith
Telephone number                           020 7116 2913
If a connected EFM, name of
offeree/offeror with which connected
If a connected EFM, state nature of
connection (Note 10)


Notes

The Notes on Form 8.3 can be viewed on the Takeover Panel's website at
www.thetakeoverpanel.org.uk

SUPPLEMENTAL FORM 8

DETAILS OF OPEN POSITIONS
(This form should be attached to Form 8.1, Form 8.1(b)(ii) or Form 8.3, as appropriate)

OPEN POSITIONS (Note 1)
Product name,     Written or  Number of securities   Exercise price   Type, e.g.     Expiry date
e.g. call option  purchased   to which the option    (Note 2)         American,
                              or derivative relates                   European etc.
Option            Purchased   250                    3,300.0000       EURO 21/12/2007
Option            Purchased   -1,000                 3,500.0000       EURO 21/12/2007
Option            Purchased   -500                   4,400.0000       EURO 21/12/2007
Option            Purchased   -350                   5,200.0000       EURO 21/12/2007
Option            Purchased   -306                   4,200.0000       EURO 21/12/2007
Option            Purchased   -300                   3,800.0000       EURO 20/06/2008
Option            Purchased   -300                   6,000.0000       EURO 21/12/2007
Option            Purchased   -275                   4,800.0000       EURO 21/12/2007
Option            Purchased   -250                   2,500.0000       EURO 20/06/2008
Option            Purchased   -250                   5,200.0000       EURO 20/03/2008
Option            Purchased   50                     5,400.0000       EURO 20/03/2008
Option            Purchased   100                    5,600.0000       EURO 18/01/2008
Option            Purchased   125                    4,400.0000       EURO 20/06/2008
Option            Purchased   -100,000               30.0000          AMER 20/06/2008
Option            Purchased   250                    3,000.0000       EURO 20/06/2008
Option            Purchased   -300,000               56.0000          AMER 15/02/2008
Option            Purchased   250                    3,800.0000       EURO 20/06/2008
Option            Purchased   250                    4,500.0000       EURO 21/12/2007
Option            Purchased   250                    6,000.0000       EURO 15/02/2008
Option            Purchased   250                    6,000.0000       EURO 15/02/2008
Option            Purchased   275                    5,000.0000       EURO 21/12/2007
Option            Purchased   306                    4,800.0000       EURO 21/12/2007
Option            Purchased   350                    4,600.0000       EURO 19/12/2008
Option            Purchased   350                    4,600.0000       EURO 19/12/2008
Option            Purchased   450                    3,500.0000       EURO 21/12/2007
Option            Purchased   500                    5,200.0000       EURO 21/12/2007
Option            Purchased   200,000                60.0000          AMER 18/01/2008
Option            Purchased   -600,000               42.0000          AMER 21/12/2007
Option            Purchased   -300,000               52.0000          AMER 15/02/2008
Option            Purchased   125                    4,400.0000       EURO 20/06/2008



Notes

1. Where there are open option positions or open derivative positions (except for CFDs), full details should be given.
Full details of any  existing agreements to purchase or to sell  should also be given on this form.

2. For all prices and other monetary amounts, the currency must be stated.

For details of the Code's dealing disclosure requirements, see Rule 8 and its Notes which can be viewed on the Takeover
Panel's website at www.thetakeoverpanel.org.uk