Washington: US President Barack Obama has said he welcomes the first indictment in the assassination of former Lebanese Prime Minister Rafik Hariri.

Obama called the indictment by a UN tribunal an important step toward ending the era of impunity for murder in Lebanon and achieving justice for its people.

He called on all Lebanese leaders and factions to preserve calm and exercise restraint.

The president said the Special Tribunal for Lebanon must now be allowed to continue its work without interference and coercion.

"Any attempt to fuel tensions and instability, in Lebanon or in the region, will only undermine the very freedom and aspirations that the Lebanese people seek and that so many nations support," he said.

US Secretary of State Hillary Rodham Clinton said those who oppose the tribunal "seek to create a false choice between justice and stability in Lebanon" we reject this.

"We are confident that the tribunal will continue to operate according to the highest standards of judicial independence and integrity. We call on all parties to promote calm and continue to respect the tribunal as it carries out its duties in a professional and apolitical manner."