Britain's Mo Farah says he could compete in the marathon at the 2020 Olympics if he feels confident of winning a medal.
Farah retired from the track in August to focus on road racing and has been coy about his Olympic future.
The 34-year-old had previously hinted he might not race for Britain again, but Farah hasn't completely ruled out the opportunity of going for gold in Tokyo.
Speaking after receiving his knighthood from the Queen at Buckingham Palace on Tuesday, the four-time Olympic champion said: "If I'm capable of getting a medal or close to a medal (in Tokyo), you will see me."
He has been retained on British Athletics' World Class Performance Programme despite doubts over his Olympic plans.
But, now living in London after splitting from controversial coach Alberto Salazar, Farah is currently more concerned with winning the London Marathon.
"For me it is the biggest marathon in the world, and it is going to be tough. Mo Farah ain't going to turn up and win... it's going to be hard to run," he said.
Quizzed on whether he had taught the Queen to do his famous 'Mobot' celebration, Farah laughed, saying it was "far too rude - not in Buckingham Palace".