The United States has recalled its ambassador to Syria after the murder of former Prime Minister Rafik Hariri of Lebanon, State Department spokesman Richard Boucher said at a briefing on Tuesday.

"The secretary has decided to recall the U.S. ambassador to Syria, Margaret Scobey, for urgent consultations following the brutal murder of former Lebanese Prime Minister Rafik Hariri on February 14th," Boucher said.

The ambassador will be returning imminently to Washington from Damascus, Boucher said.

"Following the murder of former Prime Minister Hariri, Ambassador Scobey delivered a message to the Syrian government expressing our deep concern as well as our profound outrage over this heinous act of terrorism," he added.

The United States has strongly condemned the murder of the former Lebanese prime minister and said those responsible for the murder must be punished.

Hariri was killed in a powerful explosion in central Beirut on Monday. The explosion, apparently caused by a car bomb, occurred around 1:00 p.m. (1100 GMT) when Hariri's motorcade of four black limousines escorted by jeeps was passing by in the seafront area of the capital.

Hariri died at American University Hospital, together with eight others.