Arab leaders have set out their support for Lebanon after an exchange of fire along the southern border with Israel killed at least three Lebanese soldiers and one Israeli commander.
Neighbouring Syria condemned the violence, which also left a Lebanese journalist dead, as a "heinous aggression" by Israel, while Egypt and Jordan both expressed their solidarity with Lebanon's government.
"President Assad considers that this aggression proves once more that Israel has always been seeking to destabilise security and stability in Lebanon and the region," Syria's state-run news agency said.
Western leaders, meanwhile, urged calm from both sides and appealed for them to maintain the ceasefire that has been in place along the border since Israel fought a two-month war Lebanon's Hezbollah movement in 2006.
UN Security Council Resolution 1701 ended the conflict and boosted the UN Interim Force in Lebanon (Unifil), charged with overseeing a truce between the two sides.
Saad al-Hariri, Lebanon's prime minister, made a string of phone calls to world leaders, including Nicolas Sarkozy, the French president, Hosni Mubarak, the Egyptian president, Ahmet Davutoglu, Turkey's foreign minister, and Samir Rifai, Jordan's prime minister, following the cross-border shooting.
Rifai emphasised Amman's support for Beirut, but warned of the effect any further clashes could have on attempts to work towards peace in the region.
"Rifai expressed Jordan's support for Lebanon, saying the kingdom rejects any aggression against Lebanon," the state-run Petra news agency said.
"He and Hariri stressed the need to avert more conflicts in the region that would obstruct peace efforts."
After a cabinet meeting, the Jordanian cabinet, which signed a 1994 peace treaty with Israel, released a statement saying it was "deeply concerned about the dangerous escalation in Lebanese territory," Petra said.
Ahmed Aboul Gheit, the Egyptian foreign minister, urged Unifil to calm the situation and prevent any further violations of resolution 1701 by the Israelis.
He said that his ministry had called the US, France and the UN to urge their immediate intervention in applying pressure on Israel.
Israel's long-term enemies in Iran and the Palestinian Hamas movement also took the opportunity to criticise the Israeli army's actions.
"We stand with Lebanon and pay tribute to its national army which has the right to counter the repeated Zionist violations in order to defend the land and Lebanese sovereignty"
"The Islamic republic of Iran strongly condemns the Zionist regime's incursion in the southern regions of Lebanon which resulted in the martyrdom of a handful of children of the Lebanese army," the Iranian foreign ministry said in a statement carried by state news agency IRNA.
It said the "hysterical assault" by Israel has raised an existing concern of "a new adventure" by Israel against Lebanon.
Hamas urged the United Nations "to assume its responsibilities and contain Israeli arrogance and aggressions".
"We stand with Lebanon and pay tribute to its national army which has the right to counter the repeated Zionist violations in order to defend the land and Lebanese sovereignty," it said in the statement released in Damascus, the Syrian capital.
The US, which has long been Israel's closest ally, said it was "extremely concerned" after the clashes near the Lebanese village of Adaysseh across the border from Misgav Am in Israel.
"We deeply regret the loss of life. We urge both sides to exercise maximum restraint to avoid an escalation, and maintain the ceasefire that is now in place," Philip Crowley, the US state department spokesman, said.
"The last thing that we want to see is ... this incident expand into something more significant. And that's why ... we and others have been in contact throughout the day and are trying to make sure that it goes no further."
The UN security council held a closed-door session on the incident on Monday called on "all parties to practice the utmost restraint".
"The members of the security council expressed their deep concern about today's incident along the Blue Line which led to casualties on both sides," Vitaly Churkin, Russia's ambassador to the UN and president of the council this month, told reporters after the meeting.