Lebanon's government collapsed Wednesday after Hezbollah and its allies resigned from the Cabinet in a dispute with Western-backed factions over upcoming indictments in the 2005 assassination of former Prime Minister Rafik Hariri.
A U.N.-backed tribunal investigating the truck bombing that killed Hariri and 22 others is widely expected to name members of the Shiite militant group, which many fear could re-ignite sectarian violence that has erupted repeatedly in the tiny nation.
Hezbollah's walkout ushers in the country's worst political crisis since 2008 in one of the most volatile corners of the Middle East.
Lebanon's 14-month-old government was an uneasy coalition linking bitter rivals: a Western-backed bloc led by Hariri's son Saad and Hezbollah, which is supported by Syria and Iran and maintains an arsenal that far outweighs that of the national army.
Disputes over the tribunal have paralyzed the government for months, with Hezbollah denouncing the court as a conspiracy by the U.S. and Israel and urging the prime minister to reject any of its findings. But Hariri has refused to break cooperation with the Netherlands-based tribunal.
Now, the chasm between the two sides is deepening with Hezbollah accusing Hariri's bloc of bowing to the West. Hezbollah's ministers timed their resignations to coincide with Hariri's meeting with President Barack Obama in Washington, forcing him to meet the American president as a caretaker prime minister.
Western governments have worked to strengthen the central government since Israel and Hezbollah fought a devastating 34-day war in 2006, but they also have expressed concern about the balance of power with the heavily armed militant group.
The U.S. classifies Hezbollah as a terrorist organization.
A White House statement said Obama commended Hariri for his "steadfast leadership and efforts to reach peace, stability and consensus in Lebanon under difficult circumstances."
U.S. Secretary of State Hillary Rodham Clinton said Hezbollah's actions are "a transparent effort ... to subvert justice and to undermine Lebanon's sovereignty and independence."
"No country should be forced to choose between justice and stability," Clinton said while traveling in Doha, Qatar. "The Lebanese people deserve both."
Hariri's office had no immediate comment on the walkout that brought down his government, but they said he was heading to France to meet French President Sarkozy before heading back to Beirut. France, Lebanon's former colonial power, is a major player in Lebanese politics.
The immediate trigger for the Hezbollah withdrawal was the failure of talks between Syria and Saudi Arabia, a Hariri ally, to try to find a compromise over the tribunal.
There had been few details about the direction of the Syrian-Saudi initiative, but the talks were lauded as a potential Arab breakthrough, rather than a solution offered by Western powers.
"This Cabinet has become a burden on the Lebanese, unable to do its work," Jibran Bassil, who is resigning his post as energy minister, said at a news conference, flanked by the other Hezbollah-allied ministers who are stepping down. "We are giving a chance for another government to take over."
Bassil said the ministers decided to resign after Hariri "succumbed to foreign and American pressures" and turned his back on the Syrian-Saudi efforts.
Calls to the tribunal seeking comment Wednesday were not immediately returned.
U.N. Secretary-General Ban Ki-moon "is monitoring closely developments in Lebanon, where the situation is fast evolving," U.N. spokesman Martin Nesirky said.
Hariri formed the current national unity government in November 2009 after his bloc narrowly defeated the Hezbollah-led opposition in elections. But it has struggled to function, and in the past two months it has met only for a few minutes because of the dispute over the tribunal.
Rafik Hariri's assassination in a massive truck bombings both stunned and polarized Lebanese. He was Lebanon's most prominent politician in the years after Lebanon's 1975-1990 civil war -- a Sunni who was a hero to his own community and backed by many Christians who sympathized with his efforts in the last few months of his life to reduce Syrian influence in the country.
A string of assassinations of anti-Syrian politicians and public figures followed, which U.N. investigators have said may have been connected to the Hariri killing.
The tribunal has not said who it will indict, but Hezbollah leader Sheik Hassan Nasrallah has said he has information that members of his group will be named.
Now that the government has fallen, President Michel Suleiman will likely hold a meeting with the parliament speaker marking the beginning of consultations with lawmakers to name a prime minister-designate.
It is possible that Saad Hariri will get the largest numbers of backers given that he heads the largest bloc in parliament, but he could not build a coalition again without appealing to Hezbollah and its allies.