NAIROBI, April 11 (Xinhua) -- Kenyan Olympic marathon champion Eliud Kipchoge is not ruling out a world record attempt at the London Marathon on April 22.

He has raced sparingly since he won in Berlin in September last year.

Kipchoge is optimistic as he takes on his first marathon since winning in Berlin in October in 2:03:32.

"I feel like I'm in good form. Berlin was difficult because the weather was not good but my time showed I was in the right shape. I know I have the world record in me so we will have to wait and see what happens," Kipchoge said on Wednesday.

Kipchoge is eyeing his third victory in London having won the event in 2015 and 2016.

However, he yet again faces his strongest opponents led by London Marathon silver medallist Kenenisa Bekele of Ethiopia, Mo Farah (England) and defending champion Daniel Wanjiru of Kenya.

Bekele, Farah and Kipchoge have won a combined eight Olympic gold medals and 12 World Championship gold medals between them.

"This is a mouth-watering prospect," said event director Hugh Brasher. "Farah, Eliud and Kenenisa could all put forward a persuasive case for being the greatest of all time and now they meet for the first time over the marathon distance."

Already Wanjiru has warned his rivals that he may not have the top record going into the race, but pledged not to give up his title without a fight.

"Rule me out at your own peril. Nobody expected me to win last year and again nobody has me in mind. I however, believe in my ability and strength and hope to prove my critics wrong again," Wanjiru said.

The 24-year old won in London in April, but failed to show his ability when returned to the city to finish eighth at the World Championships.

Kipchoge, 33, has the greatest marathon pedigree. The two-time London Marathon champion is widely seen as the greatest marathon runner of his generation.

He has run an unratified marathon time of 2:00:25 and is the reigning Olympic champion.

There will also be two-time world marathon champion Abel Kirui, fourth in last year's race and London Marathon bronze medallist Bedan Karoki, who has shaken off an injury which saw him miss out on defending his RAK Half marathon title in the UAE in February.