WASHINGTON - President George W. Bush called on Friday for a "full and firm" investigation of the assassination of former Lebanese Prime Minister Rafik al-Hariri in which Syrian officials have been implicated.

With Hariri's son Saad at his side in the Oval Office, Bush also said the United States wanted to see Lebanon "free of Syrian intimidation."

No one has yet been indicted in the killing of Hariri in a truck bomb in Beirut almost a year ago, but a U.N. investigation has implicated senior Syrian officials and their Lebanese allies.

Lebanon has also detained a number of individuals identified as suspects. Damascus has denied any role in the murder which stirred anti-Syrian protests in Lebanon and set in motion the withdrawal of Syrian troops from Lebanon.

"The American people mourn the loss of your dad," Bush said. "It's very important for the investigation into your dad's death to go forward. We expect there to be a full and firm investigation and the people who are responsible for your dad's death need to be held to account."

U.N. Legal Counsel Nicolas Michel discussed with top Lebanese officials on Friday ideas for the creation of an international court to try anyone charged with Hariri's killing.

Bush, who has made promoting democracy in the Middle East a cornerstone of his foreign policy agenda, said he and Hariri discussed their "mutual desire" for Lebanon to be free.

"Free of foreign influence, free of Syrian intimidation, free to chart its own course," the president added.

Hariri, a member of Lebanon's parliament, told reporters later he was trying to arrange an international donors' conference for Lebanon.

"We're working on setting the date and I hope we'll get it soon," he said. (Reuters)