The USS Cole yesterday started patrolling international waters just over the horizon from the Lebanese coastline after steaming from Malta.

The eastern Mediterranean has been busy with warships from nations enforcing the truce between Hezbollah and Israel that followed the 2006 war, but the arrival of the Cole was a US statement aimed at the key patrons of the Lebanese opposition, Iran and Syria.

Washington has taken an increasingly aggressive stance towards Syria, accusing President Bashar al-Assad of sponsoring a destabilising role in Lebanon, which has been without a functional parliament for 16 months and without a head of state since September.

The deadlock between the ruling faction and the Hezbollah-led opposition has devastated the Lebanese economy in the past year, and shows little sign of being resolved, despite efforts by mediators.

Hezbollah is demanding increased representation in Lebanon's parliament, which would probably give it a veto over key legislation and government appointments.

The campaign is seen by supporters of the ailing Government as a bid by Syria to reassert its influence in Lebanon, which it was forced to leave in mid-2005 in the wake of a revolt that followed the assassination of former prime minister Rafik Hariri.

Former Lebanese president Amin Gemayel, a key government backer, said yesterday that Michel Aoun, leader of the Christian faction that has allied with Hezbollah, has demanded veto power in the next cabinet.

"The veto power demand does not only aim to block decisions taken by the parliamentary majority," he said. "It also aims to cancel or block the role of the elected president."

The parliamentary Speaker, key opposition figure Nabil Berri, has 15 times postponed a scheduled sitting to elect a new president, despite both sides agreeing on a candidate, army chief Michel Suleiman.

The Arab world has become nervous about Lebanon's stability, which threatens to pitch the fragile nation's competing factions and sectarian groups against each other.

Jordan and Saudi Arabia fear fighting in Lebanon could draw in neighbouring countries, and are alarmed at what they see as a power bid by Iran.