Lebanon's political crisis moved toward a new danger point Saturday as the U.S.-backed government approved an international tribunal for suspects in the 2005 assassination of a former prime minister Rafik Hariri despite warnings of mass protests by its opponent Hezbollah.

Last-ditch attempts to reach a compromise between the government and the pro-Syrian camp, led by Hezbollah, appeared to fail Saturday as the Cabinet moved forward with its meeting on the U.N-created court.

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The tribunal is a key bone of contention in the power struggle between allies and opponents of Syria in Lebanon. Anti-Syrian forces — mainly Christian and Sunni Muslim — dominate the government, but are facing a campaign by the mainly Shiite pro-Syrian camp to bring the government down.

The political crisis became potentially explosive this week with the assassination of an anti-Syrian politician, raising worries of more violence that could tear apart the country's fragile sectarian seams.

The anti-Syrian bloc brought out some 800,000 people for a mass rally at the funeral of the politician, Pierre Gemayel, on Thursday. Hezbollah has shown it can bring out similar numbers for its protests — and if it goes ahead with its threatened demonstrations, many fear it could start a spiral of street action.

Earlier Saturday, two key anti-Syrian Lebanese politicians met with Parliament Speaker Nabil Berri, an ally of Hezbollah and a Syria supporter, in an apparent attempt to find a compromise.

U.S.-backed Prime Minister Fuad Saniora offered to put off the contentious Cabinet vote for several days if six pro-Hezbollah ministers who quit the government earlier this month return. Hezbollah demands that the government be changed to give it and its allies more power, or else it will launch mass protests to topple Saniora.

But the reconciliation bid appeared to have failed, and the Cabinet meeting approved a U.N. draft for the tribunal.

"Unfortunately, no agreement was reached because each side stuck to its position," Information Minister Ghazi Aridi said after the Cabinet meeting.

The Cabinet approval "now puts the opposition before its options to confront the government. The time and the place will be decided," Sheik Hassan Ezzeddine, a senior Hezbollah official, said after the vote when asked if Hezbollah would carry out its threatened protests.

"The government represents part of the Lebanese people, not all of them. Its decisions are void," he told Al-Arabiya television.

In the eyes of Hezbollah, the approval of the tribunal amounts to a rejection of its demands for a greater representation in the Cabinet. The Shiite militant group and Lebanon's pro-Syrian president, Emile Lahoud, have denounced the current government as unconstitutional, because the constitution underlines that the government must represent all of Lebanon's main communities.

Hezbollah leader Sheik Hassan Nasrallah and Berri issued a statement Friday evening renewing the threat of protests. They said they would use "all democratic and legal means" — a reference to peaceful demonstrations — to reach their goal of gaining a greater presence in the Cabinet, one that would effectively give them veto power over government decisions.

Saniora insisted the approval of the tribunal was not meant as a "provocation" against Hezbollah and its allies, according to a statement read by Aridi after the vote.

"It is in fact based on Lebanese unanimity on the creation of this tribunal and the Lebanese who are yearning to protect Lebanon, bolster its democratic freedoms and national security and bring it out of the cycle of killings and assassinations," Saniora said according to the statement.

Aridi underlined the government's "respect" for Hezbollah's opinion, but insisted, "We will not give up our goals."

The information minister said the government would allow nonviolent protests by Hezbollah, but if they spawned out of control, he warned, "this would leave negative repercussions on all of Lebanon given the current tensions in the country."

For opponents of Syria, the court is a major priority, and they hope it will uncover the truth behind the February 2005 assassination of Hariri in a massive bomb blast that killed 22 others, which they accuse Damascus of orchestrating. Syria has denied any role in the killing.

The court, which will sit outside Lebanon and have a majority of non-Lebanese judges, is to try four Lebanese generals — top pro-Syrian security chiefs under Lahoud including his Presidential Guard commander, who have been under arrest for 14 months, accused of involvement in Hariri's murder.

The U.N. investigation into Hariri's death has also implicated Brig. Gen. Assaf Shawkat, Syria's military intelligence chief and the brother-in-law of Syrian President Bashar Assad. But Shawkat is not in custody.

Hariri's death was the first in a string of attacks that killed five other prominent anti-Syrian figures — with Gemayel the most recent, in a bold daytime shooting on Tuesday. Many Lebanese blame Syria in all the killings, which Damascus denies.

Since Gemayel's assassination, some ministers in Saniora's Cabinet have moved into the heavily guarded prime minister's building in downtown Beirut, fearing more slayings.