• Briton’s first race for six months will be in Vitality Big Half • ‘I want to continue running and getting medals for my country’

Mo Farah has denied that his move to the marathon is motivated by money and says he is increasingly hopeful he can challenge for a medal at the Tokyo Olympics in 2020.

The 34-year-old, who will run his first race for nearly six months at Sunday’s Vitality Big Half in London, is rumoured to have agreed a large six-figure package with London marathon organisers, which includes running in the 2018 and 2019 races.

History made as every athlete in a 400m heat is disqualified at world indoors Read more

But Farah, who will race 13.1 miles against his fellow Briton Callum Hawkins and last year’s London marathon winner, Daniel Wanjiru, said that his desire to prove himself over 26.2 miles matters far more than anything else. “I wouldn’t be competing if I didn’t enjoy running,” he said. “You have to set yourself a target. If you look at every great athlete, like Haile Gebrselassie, they have succeeded when they have stepped up to a marathon.”

Farah, who finished a disappointing eighth in his only completed marathon, in 2014, said he was in good condition after arriving in London from his training camp in Ethiopia on Thursday and that he was not concerned about switching from running in temperatures in the high 20s to close to freezing.

“Coming down from 10,000 feet, I should have an advantage,” he said. “I’ll wear some good layers – it should be all right. And you can’t pull out because of bad weather. I’m going to race no matter what.”

Eliud Kipchoge to give Mo Farah ultimate test in 2018 London Marathon Read more

Farah also said his relationship with his new coach, Gary Lough, was going well, despite his fiery reputation. “Gary is a great coach. The last six weeks we’ve got to know each other.”

Farah, who has been running more than 120 miles a week in training, also said he had had no contact with his former coach Alberto Salazar, who remains under investigation by the United States Anti-Doping Agency.

Salazar took Farah from a good athlete to a dominant one but Farah seems confident that under Lough, the husband and former coach of the women’s marathon world record holder, Paula Radcliffe, he can improve as a marathon runner.

“I’m not going to give away secrets,” Farah said. “But training for 5,000m and 10,000m is different to marathon. But I’m happy with what we’ve done – it’s exciting. I’m definitely more confident now.

“I ran 2:08 in 2014 and the aim is to improve on that. I definitely want to continue running and getting medals for my country.”

When asked what it would take to run at Tokyo, Farah said: “Mainly mixing with the guys. If you’re not mixing with the guys and being close to winning medals, it would be hard to just turn up and make up the numbers.

“But over the next couple of years the aim is to learn about the marathon and get better at it. On the track, I started building and coming up with tactics and ways to win – in the marathon, you have to work on your weakness and get stronger.”