Siniora said unity was essential to overcome tough challenges ahead, especially post-war reconstruction, the extension of state authority over the whole of Lebanon, and the implementation of long-awaited reforms.

Special report

A series of reports on the Middle East one year after the war in Lebanon

He called for a presidential election to find a successor to his rival Emile Lahoud to be held on time, before the formation of a national unity government as demanded by the opposition.

Possible split

Some opposition figures, having failed to force a new unity cabinet through protests, are threatening to create a second government unless agreement is struck on a parlimentary vote to elect a successor to the Syrian-backed Lahoud.

Siniora also called for the army to be strengthened to put a "final end" to the Fatah al-Islam "criminal gang" fighting Lebanese troops in the north of the country.

At least 174 people, including 86 soldiers and at least 68 Fatah al-Islam fighters, have been killed in the battles around the Nahr al-Bared Palestinian refugee camp in the deadliest bloodletting since the civil war that ended in 1990.

The standoff between the government and opposition has also paralysed political life, since six ministers, seen as pro-Syrian, stepped down last November in protest at the government’s approval of a UN tribunal to try suspects in the murder of former prime minister Rafik al-Hariri.