Olympic officials were forced to erect a screen between Lebanon's and Israel's judo fighters on Friday after the Lebanese refused to train on the same mat, the Israeli Olympic team said on Friday.
The incident arose after Lebanon's two judokas found themselves next to the five Israelis during practice at the official training venue in Redbridge, in east London, said Nitzan Ferraro, spokesman for the Israeli Olympic Committee.
"We started to practice. They came and they saw us - they didn't like it and they went to the organisers," Feraro told Reuters. "They put up some kind of wall between us. Everyone went on and there was no interaction between us."
The Lebanese Olympic Committee could not immediately be reached for comment.
Organisers of the judo competition said there were always screens available so that competing athletes and their coaching staff would not be able to spy on each other's training.
Lebanon has for decades been under the influence of Syria, a bitter enemy of Israel, and the two have technically been at war since 1948.
The last military confrontation involving the two countries took place in 2006 when Israel launched an offensive against the Shi'ite Hezbollah guerrilla group, an Iranian-backed faction which holds great influence in Lebanese politics, after Hezbollah launched thousands of rockets at the Jewish state.
The Israel-Lebanon border has been largely quiet since then.
Ferraro said the incident had not been a big deal for them.
"It didn't matter for us. We don't mix politics and sport. We had no problem," he said.
Lebanon's Caren Chammas and Israel's Alice Schlesinger will both compete in the women's -63kg category next Tuesday but could only meet in the final, an eventuality organisers believe is highly unlikely.
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