Iraqi Kurd Yayha Latif al-Salhi said on Tuesday that his family had phoned him to say they were about to be expelled from Jordan.
He believes that his relatives will face persecution if returned to Iraq and alleges that one brother and his family have already been kidnapped by Iraqi agents.
Plastic surgery
Mr al-Salhi says he underwent plastic surgery to look like the president's son Uday and worked as his double for several years before fleeing Iraq.
According to the book he wrote about his experiences, both he and Uday were born in June 1964 and went to the same school.
The foreign doctors who performed the surgery put a dimple in his chin and altered his teeth so that he would have the same speech defect as Uday, he said.
Uday Hussein has a fearsome reputation in Iraq.
Assasination attempt
He is one of the most powerful figures in Baghdad, owning his own television station and newspaper.
In 1996 he survived an assasination attempt.
Mr al-Salhi fled Iraq in 1992 and now lives in the Irish republic.
Amnesty International has appealed to the Jordanian government on behalf of the family.
But Jordan's information minister Nasser al-Lawzi told the BBC that the Jordanian government does not deport people to Iraq against their will.
The Irish consul in Amman, Salim Sa'ad, confirmed that the family had applied for visas to go to Ireland.
They were in the process of claiming asylum in Jordan when they were allegedly expelled.
A spokeswoman for the United Nations High Commissioner for Refugees said, however, that the family's application for asylum was turned down by the Jordanian authorities several weeks ago.
Country profiles
Iraqi paper goes online
(16 May 99 | Middle East)
Uday Hussein: Playboy turned academic
(20 Oct 98 | Middle East)
Iraqi police arrest assassin suspects
(03 Aug 98 | Middle East)
Al Zawra newspaper
Iraqi News Agency
Iraq Net News Centre
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United Nations High Commissioner for Refugees
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