Lewis Hamilton said his desire to win will be the decisive factor in where he drives next season.
Heading into this weekend's Italian Grand Prix, Hamilton has been at the center of speculation that he will leave McLaren at the end of the season and move to Mercedes.
Hamilton declined to comment specifically on his future today but said "I want to win. You always want to win, that's why most drivers exist and that's why teams exist. It's just making sure you're in the right place to do so.
"I don't have a deadline, but obviously I need to decide before the end of the season. I'm in a great position and I need to focus on preparing for these races. There's a long way to go before the end of the season. Jenson and I have shown there's good potential in the cars and the team, so that's what I'm focusing on."
McLaren are second in the constructors' championship, having won the past two races. Mercedes trails by 106 points after just one win this season.
"Mercedes and Ferrari are on one level in terms of history," Mercedes driver Nico Rosberg said. "To drive the Silver Arrow is something very, very special for any driver, and especially to win with a Silver Arrow."
Hamilton had a turbulent time at the Belgian GP last weekend. His race was ended after a wild multi-car accident caused by Lotus driver Romain Grosjean not long after the start, and he also got into trouble for posting sensitive data on Twitter.
He is hoping to put all that behind him at Monza.
"The head of the PR department asked me to take the picture off, so I did," Hamilton said. "We've moved on from it and it won't happen again.
"Jenson drove fantastically well in the last race and showed we are very competitive, and we should have a similar performance this weekend. I'm looking to pick up the pieces and get back to racing."
Button said he was "surprised" to read the speculation over Hamilton's future and believes they will still be teammates next season.
"It's the best choice for him," Button said. "Sometimes if you've been at the same place for too long it can get a bit stale, but that's not the case here. It's a great team, it always gives us a chance to win, which is what every driver wants."
Button won last weekend but still trails leader Fernando Alonso by 63 points in the championship. He admits his chances of another title this season are all but over.
"We'll hopefully do the same as last season from now on, scoring lots of points and getting a lot of podiums," he said. "There could be a lot of spreading out of points and if you have good back-to-back races you can leapfrog people and challenge.
"It's a slim chance but it's still a chance. If there's any year you can cut the gap it's this year."
Last weekend's crash saw Alonso's lead cut to 24 points over Red Bull's Sebastian Vettel. Alonso nearly had his head clipped when Grosjean's Lotus flew over him, while Sergio Perez was also forced to retire after the incident.
All drivers escaped unscathed but it has again raised the question of safety, with Michael Schumacher in favor of an enclosed cockpit.
"That has to be the future," the seven-time champion said. "Just look at how it's developed over the years, there's been massive improvements in cockpit safety, the only exposed area is the opening where the head shows, one wrong moment in time could have fatal consequences.
"That's been identified by the FIA. Jean Todt told me there had to be action and they've initiated action. For 18 months, they've had a professional group of engineers working on it. No matter what, you won't have 100 percent satisfaction as you could improve on safety but have a downside on vision, so you have to weigh it up."
For causing the accident, Grosjean was banned for one race and will be replaced by Jerome D'Ambrosio at Lotus this weekend.
"Well obviously it's been short notice," D'Ambrosio said. "I only found out on Monday really. I haven't had time to think about anything really."
Alonso and teammate Felipe Massa will be fiercely roared on by the passionate crowd at Ferrari's home grand prix. Alonso has won at Monza twice, including in 2010 with Ferrari.
"I think Monza is a special win, because for any Ferrari driver it's a lot of support that you feel from the tifosi from today until Sunday and you want to give something back to them and the best thing is obviously a race win," Alonso said.
"But even if you're not fighting for the championship, winning in Monza will be special anyway, because the podium celebration with all the people on the main straight is nice for anyone."