The F1 world champion's new three-year deal is worth £40m a year, or £770,000-a-week, and could be signed before the season's first race in Melbourne this weekend.
The Sun claims Hamilton will be paid £80m for two years with the option of a third year at Mercedes as he bids to add to his four world titles.
"At the end of the season, of course I am wondering to myself 'do I want to keep racing?' I have to ask myself that for sure,” said Hamilton in an interview before opening the defence of his title in Melbourne.
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“Even through the year I have to ask 'how long do I want to keep racing?' but I don't know at the moment.
"Do I want to go next year? Yes. Do I want to go the year after? Most likely."
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