Sir Mo Farah has declared his intention to compete in the marathon at the 2020 Tokyo Olympics.

The 35-year-old Briton is now focused on road running after last year bringing to an end a glittering track career that featured four Olympic gold medals.

Having come third in what was his second London Marathon in April, on Sunday he competes in the Chicago Marathon, taking on his former training partner Galen Rupp.

Sir Mo Farah
Farah aims to repeat Olympics success on the track in the marathon in Tokyo (Mike Egerton/PA)

And Farah was quoted by the Telegraph as saying on Friday: “As long as my body can hold up, I am definitely going to Tokyo.

“I know from my training that I am definitely capable of getting a medal. I don’t know what the colour is going to be, but I want to continue through 2020.

“A medal would definitely rank up there in terms of being a track runner and being able to do something in the marathon. In my mind, it’s something I’ve always thought I could do.”

Farah came eighth in the 2014 London Marathon before posting this year’s third-placed finish.

Sir Mo Farah
Farah has admitted he is still learning how to race marathons (Richard Sellers/PA)

The race in April saw Farah, who experienced a mix-up over water bottles and admitted he had been surprised by the pace, break the British record with his time of two hours six minutes and 21 seconds.

He added: “I am new to the marathon. It is only my third marathon and I’m still learning. As you know from my track career, it took me 10 years to mix it with the guys and win races. It is the same with the marathon.

“This race (on Sunday) is exciting, I am in great shape, so we will see what happens. Even if it is raining, it is still on. The rain isn’t a problem but the wind could be. I am confident in my training. I am in decent shape and I believe that with the right race, the European record (which is currently 2:05.48) is definitely in with a shout.

“A personal best and a win would be great, and the European record if the weather holds up.”

Farah and American Rupp, the defending champion who he will be racing against in a marathon for the first time this weekend, both attended a press conference in Chicago on Friday.

Farah said in quotes from the press conference that appeared on the Abbott World Marathon Majors Twitter feed: “This field is strong. I am the eighth fastest in this field!

“The London Marathon in April taught me a lot. Having that kind of race in London gives me a lot more confidence. What can I really do if I go sensibly?”

Farah added: “The build-up has been about us two (him and Rupp) but there are guys in this field who have run 2:04, 2:05. We’ll see on Sunday.”