"Jenson is obviously a great driver and for those teams without their full complement of drivers, he's got to be a target," Brawn told BBC radio.
"We want Jenson to stay in the team and I think we'll find a solution.
"Jenson has a contract with us but of course that contract is not the salary of a world champion, not the salary of a team that's now in a much stronger position than it was 10 months ago.
"We are working with Jenson to find a balance between what we can afford and what he feels is fair for his status and contribution he can make in the future.
"You are never 100 per cent certain but I'd say 99," he added when asked how sure he was that Button, who clinched the title in Brazil this month with a race to spare, would be staying.
Brawn said he hoped a deal could be settled within two weeks of the final race in Abu Dhabi this coming weekend, although it could come sooner.
Button took a hefty pay cut, reported at around £5 million, before the start of the season to drive for Brawn after the team emerged from the remains of the former Honda Racing with far more limited resources.
The 29-year-old was rewarded for his loyalty with a title that would have seemed impossible a year ago but he now wants to have his salary restored to a level more appropriate for a champion.
Recent media reports in Britain had suggested Button could team up with 2008 world champion and compatriot Lewis Hamilton at McLaren.
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