Lewis Hamilton says he is not sure how much longer he wants to continue in Formula One.
Hamilton starts on pole in Portimao on Sunday and is aiming to win a record 92nd Grand Prix. The 35-year-old says he wishes to continue in the sport but says "it's not going to be for a long time".
"I don't think I'm at my peak," he told Sky Sports. "I'm in a good area, for sure.
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"I still want to continue to race but I don't know how much longer it will be. It's definitely not going to be a long time before I stop, so this is a period of time where I've got to slowly work out what the future holds.
It's bright, whatever I decide to do, but it also has to be aligned with the times, it has to be aligned with my values and it has to be aligned with what the team is planning to do.
Hamilton is yet to sign a new contract with Mercedes with most of the 2021 grid almost complete. The main question appears to be over the length of deal he decides to sign.
"I haven't made any decisions," he said in Thursday's press conference.
"I do want to stay and I think when we do sit down, normally [when] we plan it's been three-year periods but of course we're in a different time. Do I want to continue for three years is also a question.
"There are many, many questions still to be answered. We're also going into a new era of car in 2022. It kind of excites me what could happen in 2022 in terms of what the cars are like."

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