Olympic athletes who boycott Israeli competitors in London this summer will be in breach of the organising committee's rules.

A spokesman for the International Olympic Committee stated categorically that refusing to compete against Israelis would represent "a serious breach of the IOC's Code of Ethics, the principles of the Olympic Charter and the Athletes Oath".

Emanuelle Moreau also said: "Refusing to participate in an Olympic event because of a fellow athlete/team's religion or nationality [would be] unsporting behaviour."

She warned athletes who were considering taking a stand against Israelis rather than competing against them, to "stay at home".

There have been several cases of athletes from Middle Eastern countries refusing to compete in international races where Israelis are present, including the comments this week by the head of the Algerian Olympic committee on the matter.

Rachid Hanifi said that if Algerian athletes were drawn against Israelis, there would be "an obligation to ask our government if we have to meet Israel in sport".

Last year the leader of the World Jewish Congress called for Iran to be suspended from international sporting events until the country allowed its athletes to race Israelis.