The 2009 world champion is out of contract with the Woking-based team after this year, but has repeatedly expressed his desire to remain with McLaren for Honda's impending return to the sport in 2015.
The Briton told reporters at the Canadian Grand Prix earlier this month there had been "no progress" on a fresh deal, but reiterated his desire to remain with the team.
Those comments were followed by McLaren Group CEO Ron Dennis telling Sky Sports he wanted to see Button "try harder" in response to the challenge of rookie team-mate Kevin Magnussen, who has outqualified him for four of 2014's eight grands prix so far.
McLaren racing director Eric Boullier has recently implemented a major restructure of the team in a bid to return it to winning ways in the longer term, but the Frenchman remained non-committal on Button's future when quizzed by AUTOSPORT.
"It's the question where I cannot say yes and I cannot say no," said Boullier, when asked by AUTOSPORT whether McLaren intended to retain Button for next season.
"We are evaluating strategies and we are lucky to have two drivers who want to commit to us for the future.
"We have contractually some options we can pick up, so we are not in a rush to decide next year or the future driver line-up."
Boullier is confident the changes he has made at the team, coupled with a new works engine partnership with Honda for next year, will improve McLaren's prospects by 2015.
"I do have confidence we will have a good car for next year, just because we addressed all the issues internally and I believe we made all the right changes," Boullier added.
"This [the Honda engine deal] is a big project and it takes months, even years, to build up.
"Having a works engine allows you to play with much more channels, data and set-up possibilities than if you have a customer engine.
"So far, everything is in order and matching the path we have until the first race of next year."
- Sports & Recreation
- Motor Racing
- Eric Boullier