Speculation mounts that Button will retire from F1

Formula One - F1 - Singapore Grand Prix 2015 - Marina Bay Street Circuit, Singapore - 17/9/15 McLaren's Jenson Button ahead of the Singapore Grand Prix Mandatory Credit: Action Images / Hoch Zwei Livepic

SUZUKA, Japan (Reuters) - Jenson Button has increased speculation he is set to retire from Formula One after telling British reporters that the 'joy' of competing was missing and he had made a decision about his future.

Media reports suggested the McLaren driver, whose wife is Japanese, was likely to announce at this weekend's Japanese Grand Prix that he would be leaving Formula One at the end of the year.