Britain's Mo Farah says he is targeting the 10,000m at the London Olympics and will wait to see how he feels before deciding whether to go for a double in the 5,000m.

“I am going to run the 10,000 for sure because it is the first race,” said 5,000m world champion Farah after winning the 5,000 at the Diamond League’s Prefontaine Classic in Oregon.

“I will see how I feel after that. It depends how I come off in the 10,000. I would like to be fresh and not have any niggles.”

Farah’s time of 12 minutes 56.98 seconds in the US was the fastest in the world this year and easily beat the defending Olympic champion, Ethiopia’s Kenenisa Bekele, who finished in fourth place.

Kenya’s Isaiah Koech came second with American Galen Rupp in third.

Farah’s time was the second fastest he has run over 5,000m and broke the Eugene meeting record.

“The crowd got behind me. I was really pleased,” said the 29-year-old Farah. “It was kind of an up and down pace. I started reasonably good then slowed down in the middle and then towards the end I picked it up.

“The conditions were a little windy so I wasn’t as perfect as what I wanted. But at the end of the day, I think the most important thing was to get a win under my belt.”

Despite having won silver in the 10,000m as well as 5,000m gold at the World Championships in Daegu, South Korea, last year, Farah insisted he would not save anything for the 5,000m which comes seven days later in the Olympic schedule this summer.