The United States is keeping a close eye on the situation in Lebanon after Prime Minister Saad Hariri’s government collapsed following the resignation of Hezbollah and its allies, the Pentagon said Thursday.

Eleven ministers withdrew from Hariri’s government Wednesday evening, providing the minimum number of resignations to automatically dissolve the 30-member Cabinet.

Accelerating developments have sparked a flurry of international activity to contain the fragile situation in Lebanon. “We do know that political tension, unrest and especially any violence that might follow are threats to regional stability and security,” said Pentagon spokesman David Lapan.

The resignation was linked to a long-running dispute over the U.N.-backed Special Tribunal for Lebanon, which is reportedly set to indict high-ranking Hezbollah operatives in the 2005 assassination of ex-Prime Minister Rafik Hariri, Saad’s father.

Asked whether Washington would send any warships to patrol the waters off Lebanon, he said no ships had been sent yet. “The Department of Defense and the U.S. government desire that all parties use peaceful means to resolve the situation. We continue to monitor the situation very closely,” he added.

Lapan said the United States, which is a major supplier of military aid to Lebanon, has a valuable relationship with the Lebanese Armed Forces.

“We are committed to do what we can to strengthen the sovereignty of the institutions as well as of the government of Lebanon,” he said.

The U.S. regional ally, Israel was reportedly carefully watching developments in Lebanon as well, a senior government official told A.F.P. Thursday.

“This crisis is an internal Lebanese issue. But we are following everything that is happening with vigilance,” the official said, stressing Israel was “clearly opposed to any escalation” in the situation along the northern border.

Israeli troops in the north were on alert over worries that the political turmoil in Lebanon might spill over into renewed violence on their shared border.

Israeli Foreign Minister Avigdor Lieberman said Hezbollah’s sudden withdrawal from the Lebanese government is an attempt to blackmail the international community to prevent the release of the indictment.

Meanwhile, Arab states called on the Lebanese to exercise self-restraint with Egypt voicing a message of support to Hariri.

Jordan’s Foreign Minister Nasser Judeh urged all Lebanese parties to avoid an “escalation” of the crisis. “Jordan is closely following the developments in Lebanon, urging restraint and calling on all Lebanese to avoid an escalation,” he was quoted as saying by the state-run Petra news agency.

His Egyptian counterpart Ahmad Abu al-Gheit, praised Hariri during a phone conversation with the latter.

“We commend Hariri’s constructive positions during the past phase that were aimed at preventing Lebanon from being exposed to the dangers of further escalation,” he was quoted as saying.

Echoing Judeh, Abu al-Gheit called on the parties to exercise “restraint” and to “act within the framework of state institutions to contain the crisis.”

Arab League chief Amr Moussa expressed concern that Lebanon could again descend into chaos. “It is bad. It is tense. It is threatening,” he said of the situation.

“All of us have to work together in order to reach some kind of compromise,” he told reporters in Doha, Qatar.

Similarly, E.U. foreign policy chief Catherine Ashton expressed concern over the situation in Lebanon and called for a negotiated solution to the political crisis.

“I am concerned by the situation in Lebanon. I want to reiterate our support for the government of national unity,” Ashton said in a statement.

“I call on all political actors to work constructively to seek a negotiated solution to the current situation,” she said.