Admiral Mike Mullen, chairman of the US joint chiefs of staff, has said the military operation in Libya called for by the UN Security Council is not aimed at regime change - adding that a "stalemate" could well exist, leaving Muammar Gaddafi in power.
The 64-year-old admiral also said that no-fly zone had "effectively been established", as Gaddafi's planes had not taken to the skies following Saturday's overnight shelling of dozens of targets in northern Libya.
Anti-aircraft fire was also heard in the Libyan capital on Sunday night, indicating a second wave of incoming jets. Tracer rounds and machine-gun fire was also heard, though there has been no confirmation yet of further attacks.
"In the first 24 hours, operations have established the no-fly zone. French air planes are over Benghazi as we speak and will do that on a 24/7 basis. The operations have taken out some ground forces near Benghazi, taken out air defences, some of his control nodes, some of his airfields, I don’t have all damage assessments, but so far [it's been] very very effective," he said.
Gaddafi "was attacking Benghazi and we are there to stop that ... we are ending his ability to attack us from the ground, so he will not continue to execute his own people."
Mullen, the most senior officer in the US military, denied that any civilians had been killed in the bombardment, which saw some 110 cruise missiles being shot from American naval vessels in the Mediterranean sea.
Libyan state TV has reported that death toll from the air strikes has risen to more than 60.
It's understood that 20 of 22 Libyan targets were hit in the overnight assault, "with varying levels of damage", a military source told Reuters.
Mullen also said the US would be handing command of the operation to "a coalition" of militaries, with support coming from the Arab world, as well as NATO members.
"There are forces, airplanes in particular from Qatar, who are moving into position as we speak. There are other countries who have committed - I'd rather have them publicly announce that commitment.
"It was a significant point when the Arab League voted against this guy. This is a colleague [of theirs], and we’ve had a significant number of coalition countries who've come together to provide capability."
Amr Moussa, secretary-general of the Arab League, said on Sunday that when the organisation endorsed a no-fly zone "what we wanted was the protection of civilians and not the bombardment of more civilians".
Hours after the international coalition launched air attacks on his forces, Muammar Gaddafi, the longtime Libyan leader, responded pugnaciously, vowing to defeat foreigners who he said had no right to interfere in the North African nation's internal affairs.
In a roughly 15-minute address on Sunday, his second since the air raids began and during which he never appeared on screen, Gaddafi promised a "long war" that his forces would win. The promise to fight came after Libyan foreign minister Musa Kousa responded to a United Nations resolution authorising force to protect civilians by promising to institute a cease fire. A second ceasefire was announced by a military spokesman on Sunday evening.
"We will fight for every square in our land," Gaddafi said. "We will die as martyrs."
Gaddafi, the de-facto leader of the country for more than four decades, declared that Libyan "people are behind me and ready for all-out war", and repeated his claim that his regime had "opened the depots" and distributed weapons among the populace.
He drew allusions to other US-led wars, including Vietnam, as well as the Crusades, saying that air attacks by French, US and British forces amounted to a "cold war" on Islam.
He also promised retribution against Libyans who sided with the foreign intervention.
"We will fight and we will target any traitor who is co-operating with the Americans or with the Christian Crusade," he said.
Gaddafi mentioned the wars in Vietnam and Iraq, as well as the bloody US intervention in Somalia and the ongoing campaign to capture or kill al-Qaeda leader Osama bin Laden.
All, he said, were examples of the kind of defeat the US was about to endure in Libya.
"You don't learn," he said. "You're always going to be destroyed."