Lebanon has expressed surprise at US demands that it track down a hijacker freed from jail in Germany.
The US says Hammadi did not serve a full German life sentence
Mohammed Ali Hammadi, 41, returned to Lebanon last week after serving 16 years for killing a US Navy diver while hijacking a TWA jet in Beirut in 1985.
The US wants Hammadi to face further imprisonment in the US.
But Lebanon's prime minister questioned US requests for Beirut to hand over Hammadi. The two countries are emerging allies but have no extradition treaty.
"The US could have initially asked Germany to hand him over. Why are they asking us," asked Prime Minister Fuad Siniora asked.
"It would have been better to ask for his extradition when he was in Germany.
"He served his sentence in Germany and there are measures that will be completed in Lebanon. Why are they asking us now?"
US officials said that the country's extradition treaty with Germany did not permit them to seek the extradition of someone on charges for which they have already served time in prison.
Instead Attorney General Alberto Gonzales made representations to Germany urging Hammadi's continued detention, the US said.
TWA Flight 847 was hijacked between Athens and Rome
When he was released, the US vowed to recapture him and bring him to trial.
"At this point I think what I can assure anybody who's listening, including Mr. Hamadi, is that we will track him down," State Department spokesman Sean McCormack has said.
"We will find him and we will bring him to justice in the United States for what he's done."
'Served his time'
The brother of the murdered diver, Robert Dean Stethem, has called Mr Hammadi's parole "absolutely disturbing".
His mother Patricia said of Mr Hammadi: "We'll be after him. We won't let it rest."
TWA Flight 847 from Athens to Rome was hijacked on 14 June 1985 and forced to land in Beirut. The plane's passengers were kept as hostages for 17 days as the aircraft flew between Beirut and Algeria twice.
The hijackers demanded the release of 17 members of Hezbollah and the Iraqi Islamic Daawa Party detained in Kuwait for attacks that killed six people in 1983.
During the incident, the hijackers killed US Navy diver Mr Stethem and dumped his body on to the runway apron at Beirut Airport.
Mr Hammadi was arrested at Frankfurt Airport in 1987 when he tried to smuggle liquid explosives into Germany.
Mr Hammadi's three accomplices in the hijacking - Hassan Izz-Al-Din, Ali Atwa and Imad Mughniyeh - are still at large.