The Brazilian was persuaded to return to F1 to partner rookie Lance Stroll after Valtteri Bottas moved to Mercedes to replace Nico Rosberg.

Massa, who signed on a one-year deal, has scored all of Williams's 20 points in the opening six races.

When asked by Motorsport.com if his form this season is encouraging him to stay on for what would be a 16th season, Massa said: "Yes. If I have the opportunity to stay in the direction I am or the direction I think is correct for me, I stay.

"Otherwise, no. I was saying the same last year."

Massa said he is enjoying F1 again, particularly the 2017 generation of cars, and feels like he is delivering.

"I'm relaxed, there's no pressure and I'm just trying to enjoy it," he said. "I was doing the same [last year], but I don't know, maybe things change for better and the way I feel and the way I'm working is quite relaxed.

"I'm sure I can do a really good job. I feel things are going well. I like this car, it's a lot more close to my driving style.

"I'm happy with the car, the way I'm driving, the way I'm feeling and the work I'm doing with the team. The most important thing is trying not to lose points."

Massa, who has scored points in four out of six races this season, said he is not setting a deadline for when he has to make a decision about 2018.

"I'm not considering anything, to be honest," he said. I just enjoy myself race by race and we see what is going to happen. I have no idea what is going to happen."