BEIRUT (Reuters) — A bitter power struggle between Hezbollah and leaders of the Western-backed Beirut government threatens to spill into the streets 11 weeks after Lebanon emerged from a devastating war with Israel.Hezbollah leader Sayyed Hassan Nasrallah vowed on Tuesday to stage peaceful protests demanding fresh elections unless his opponents agree to a national unity government by mid-November.

In a political atmosphere soured by mutual acrimony, such demonstrations could degenerate into violence, perpetuating instability and crippling prospects for postwar recovery.

“It’s a very volatile situation,” said Michel Naufal, foreign editor of al-Mustaqbal newspaper owned by the family of assassinated former Prime Minister Rafik al-Hariri.

Both sides feel betrayed and threatened.

Hezbollah accuses the anti-Syrian “March 14” coalition of failing to back it during the war and of supporting US-Israeli demands for the disarmament of its Shi’ite Muslim guerrillas.

Nasrallah said the coalition was bent on expanding the mandate of UN peacekeepers in the south to other parts of Lebanon to neutralise Hezbollah’s military capacity.

The March 14 group, which won its parliamentary majority partly as a result of its electoral alliance with Hezbollah, blames Nasrallah for dragging Lebanon into a disastrous war at the behest of its Syrian and Iranian allies.

The struggle reflects a wider conflict in which Hezbollah follows an Islamist-Arab nationalist agenda of resistance to US-Israeli “hegemony” and pro-Western Arab leaders.

Hezbollah’s Sunni Muslim, Druze and Christian critics fear this will draw Lebanon into a Syrian-Iranian axis and shatter hopes for independence after Syria withdrew its troops last year following mass protests over Hariri’s February 14 assassination.

“They are fighting over matters of high principle,” said Hilal Khashan, a political science professor at the American University of Beirut. “Each wants to get rid of the other.”

Nabih Berri, Parliament Speaker and Amal leader, has asked the two sides to meet next week to defuse the crisis.

But no sign of a compromise has yet emerged over Nasrallah’s demand that Hezbollah and its allies <\m> the Shi’ite Amal faction and Christian leader Michel Aoun’s Free Patriotic Movement <\m> make up a third of the cabinet, enough to block any decisions.

A possible tradeoff would be for the March 14 group backing Prime Minister Fouad Siniora’s government to agree to an expanded cabinet on condition that plans proceed for a tribunal with an international character to try Hariri’s killers. The tribunal has fuelled a side-conflict between the March 14 group and pro-Syrian President Emile Lahoud, whose removal is one of the majority coalition’s key demands.

A new president must be elected by parliament within the next 12 months, setting the stage for another struggle, heralded by Nasrallah’s threat to demand early legislative polls under a revised electoral law if he does not get his way on the cabinet.

“If there is no compromise by the March 14 group, Hezbollah will try to overthrow the government, which will be highly destabilising because Hezbollah is questioning the system’s legitimacy,” said Amal Saad Ghorayeb, an expert on Hezbollah.

“They are saying parliament and the government are not representative at the popular level,” she added.

A previous “national dialogue” organised by Berri before the July-August war already suggested that flaws in representation prompted the recourse to a forum outside parliament and cabinet.

Hezbollah and Amal have five ministers in the cabinet, but Aoun, the election victor in Maronite Christian heartlands, was excluded and has now aligned himself with the pro-Syrian Shi’ite factions — despite his past record as a fierce foe of Damascus.

Ghorayeb said the March 14 coalition faced an unpalatable choice in how to deal with the demand for a unity cabinet.

“If they agree, they will effectively lose the ability to impose their decisions. If they refuse, the government will fall and the whole system will be delegitimised,” she argued.

UN envoy Terje Roed-Larsen has described the situation in Lebanon as worrying. “The political rhetoric shows there are very high tensions,” he told reporters in New York this week.

The spectre of street confrontations turning violent scares many Lebanese still traumatised by the 1975-90 civil war. The language some politicians are using will not reassure them.

“Protest will be met by protest. The bullet will not be confronted with a flower,” declared Akram Shuhayeb, a member of parliament and senior aide to Druze leader Walid Jumblatt.