Rival teams tried to "unsettle" Jenson Button this season by offering him alternative cockpits for 2010, according to his boss Ross Brawn.
Brawn and 2009 champion-elect Button, 29, are yet to agree terms on a bigger retainer for the British driver for 2010.
McLaren has emerged as one alternative for next season, and in an interview with BBC Radio 5 Five, Brawn hit out at some "people" who made approaches to Button in the midst of his championship campaign.
"There were people, when they became aware of Jenson's contractual situation, who tried to unsettle him during the championship," said Brawn, who confirmed that Button "has some offers" to move elsewhere in 2010.
"He knew some of those tactics were for that reason."
Brawn indicated that a replacement for the Williams-bound Nico Rosberg, believed to be the Mercedes-backed Nico Rosberg, will only be announced once the Button situation is resolved.
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