You can't.

Under FIDE rules, a draw can't be taken back.  ...

10.7

A proposal of a draw under the provisions of Article 10.6 may be made by a player only at the moment when he has just moved a piece. On then proposing a draw, he starts the clock of his opponent. The latter may accept the proposal, which is always to be taken as unconditional, or he may reject it either orally or by completing a move. A draw offer is valid until the opponent has accepted or rejected it. 

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