Europe led calls from the international community strongly condemning renewed fighting in Lebanon and said militia in Lebanon needed to be disarmed as concerns of a humanitarian crisis have increased.
The EU called for the disarmament of the Islamic militias in Lebanon as fighting continued
Hinting at the possibility of a ceasefire, a government source told dpa that "the government is keen to end the situation with the minimum civilian loses."
Fatah al-Islam, an Islamist group fighting Lebanese troops, however, said it would fight until the army stops its attacks.
"If the army continues its attacks, our fighters are ready to fight until the last drop of blood," spokesman Abu Salim Taha told the AFP news agency on Tuesday. "The ball is in the army's field, they are the ones who started the fight, and they are the ones who will stop it."
The German presidency of the European Union condemned the bloodshed and called for the disarmament of Islamic militia fighters.
In Berlin, a foreign ministry spokesman said Germany viewed the fighting with very great concern, and "condemns the attack on the Lebanese security forces in the strongest terms."
Lebanese troops are fighting the militias street by street
The renewed violence "reminded us how urgent it is that militia in Lebanon are disarmed."
Germany currently has some 3,000 soldiers patrolling the coast of Lebanon as part of a UN peacekeeping mission there.
The United Nations voiced concern about an unfolding human crisis in a Palestinian refugee camp in northern Lebanon where the army was locked in battle with Islamist extremists.
Saudi Arabia deplored the fighting at the camp and made an appeal to ensure the country's sovereignty and security.
The calls followed serious concern expressed by Russia on Sunday. "Such an upsurge of violence in an already tense situation in Lebanon gives rise to deep anxiety," the Russian foreign ministry said.
Bloodiest days since the civil war
Lebanese troops pounded Islamist militiamen in a Palestinian refugee camp on Monday, the second day of the bloodiest internal fighting since the 1975-90 civil war that has now killed at least 55 people and raised deep concerns about Lebanon's fragile security.
Britain fears al Qaeda has infiltrated the Nahr el-Bared camp
A Saudi government statement on Monday spoke of "regrettable events directed against the security and stability of Lebanon."
Saudi Arabia, one of Lebanon's principal financial backers, made an appeal to maintain "the sovereignty and stability of Lebanon and support all that is likely to consolidate its security."
Richard Cook, director of the United Nations Relief Works Agency for Palestine refugees (UNRWA), said the fighting in and around Nahr al-Bared camp was distressing.
"We are deeply concerned about the developing humanitarian crisis, particularly the danger to civilian lives," he said in a statement. "Once a ceasefire is called, UNRWA will ensure essential care, food and water will be provided to the inhabitants of the camp as well as evacuating the injured and killed."
Britain concerned at al Qaeda links
Britain backed the Lebanese military offensive in northern Lebanon in a statement by Foreign Office junior minister Kim Howells.
"I am disturbed by the fighting at the Nahr Al-Bared Palestinian refugee camp in northern Lebanon," Howells said.
Lebanese special forces continue to stage operations
"The existence of extremists sympathetic to al Qaeda in the camp is a threat to Lebanon and the broader region and the vast majority of Palestinians in that camp and others oppose them," he added. "We support the Lebanese authorities in bringing the situation under control."
Britain also condemned Sunday's bombing in east Beirut that killed one person and injured many others, he said, adding, "There can be no justification for such attacks, which only exacerbate an already tense political climate."
In Paris, French Foreign Minister Bernard Kouchner spoke with Lebanese Prime Minister Fuad Siniora on Sunday to assure him of France's solidarity, his office said.
Kouchner "expressed France's solidarity and trust in the Lebanese authorities to restore order and calm," said a foreign ministry statement.
Paris stresses support for sovereignty
During his call, Kouchner stressed the importance Paris gave to "the independence, sovereignty and stability of Lebanon" and the need to "investigate the situation, especially in Tripoli."
Lebanon has been in turmoil since the mandate of Damascus-backed President Emile Lahoud was extended for three years in 2004 under a Syrian-inspired constitutional amendment.
The country has remained split between pro- and anti-Syrian camps, with the gap widening after a series of murders of anti-Syrian figures widely blamed on former powerbroker Damascus -- accusations Syria has denied.