Iran's Arash Miresmaeili has been eliminated after failing to make the correct weight at the Athens Olympics.
Miresmaeili is a two-time world champion
But there is confusion over the affair, following the judo star's reported threat to walk out in protest when he was drawn against an Israeli opponent.
Iran has a strict policy of sanctions against Israel and forbids any contact with Israeli citizens.
Iran's President Mohammad Khatami has said Miresmaeili's act will be recorded among the nation's glories.
The International Judo Federation (IJF) said: "We're very surprised an elite player could not make his weight."
It added: "At the moment we have someone who is representing his country and did not make the weight. We have to know more about it."
The IJF's executive committee met on Sunday to discuss the case, but a spokesman said that no decision had been reached. More talks are expected on Monday.
Miresmaeili, the world champion in the under-66kg division who carried Iran's flag at Friday's opening ceremony, had been drawn to face Israeli's Ehud Vaks in the first round.
After the draw, he was quoted in Iran as saying that he had refused to face his Israeli rival in sympathy with the "oppressed" Palestinian people.
A spokesman for the Iran National Olympic Committee said it was a "general policy" of the country to refrain from competing against Israeli athletes and that Miresmaeili had simply observed the protocol.
But the IJF said it received letters on Saturday from officials of the Iranian Judo Federation denying Miresmaeili would withdraw from the Olympics on political grounds.
On Sunday Miresmaeili was weighed for the contest but was over the featherweight limit of 66kg needed to compete.
"We sent this information to the IOC," said the IJF.
"We don't know if they (the reports) are true or not true. We have to study that - at the moment we don't have the right information.
"As regards the political issue... the IJF want to promote the values of judo...
"We heard IOC president Jacques Rogge calling for the values of tolerance, solidarity, peace and friendship.
"These are the values of the IOC, these are the values of judo so we would like these values to be promoted in judo."
The IOC said that it had not received notification of any issues relating to Miresmaeili's withdrawal, but it is unhappy about any political gestures, says the BBC's Harry Peart in Athens.