Western countries say they are considering whether to take military action to help push Libyan leader Muammar Qaddafi from power and protect Libyans opposed to Qaddafi's regime from attacks by Qaddafi's forces.
The United Nations has warned of a refugee emergency in connection with the crisis, saying that some 70,000-75,000 people have fled Libya to Tunisia since February 20.
And further fighting has been reported as forces loyal to Qaddafi seek to regain areas held by protesters in Libya's west.
Reports said Qaddafi's forces had tried -- but failed -- to retake Zawiyah, a rebel-held city 50 kilometers west of the capital, Tripoli. Qaddafi still holds Tripoli and other nearby cities.
U.S. Defense Secretary Robert Gates confirmed on March 1 that several American warships have been deployed to sail toward Libya. But Gates said there was no agreement within NATO to take military action, and no decisions on force have been made by the Obama administration.
"We're obviously looking at a lot of options and contingencies," Gates said. "No decisions have been made on any other actions."
The chairman of the Joint Chiefs of Staff, Admiral Mike Mullen, expressed caution about potentially establishing a no-fly zone over Libya to prevent air attacks by Qaddafi's forces, calling it an "extraordinarily complex operation to set up."
British Prime Minister David Cameron has said the use of military force remains an option. But France and Russia say any military action would require a clear mandate from the United Nations Security Council.
Italy has meanwhile announced it will send a humanitarian mission to Tunisia to provide food and medical aid to as many as 10,000 refugees fleeing the Libyan conflict.
Melissa Fleming, spokeswoman for the UN High Commissioner For Refugees, said 14,000 people had fled across the border to Tunisia on February 28, the highest number in a single day since the crisis began.
In an interview with Western journalists, Qaddafi laughed off growing international calls for his resignation as the challenge to his government entered its third week.
The continuing clashes have prompted U.S. Secretary of State Hillary Clinton to warn that the North African country could "face protracted civil war" or "descend into chaos."
Witnesses say pro-Qaddafi troops battled for six hours overnight in an attempt to storm Zawiya from six different positions around the city. Their assaults including barrages of tank and heavy artillery fire at the western approaches of the city around dawn.
Correspondents report that the anti-Qaddafi fighters were able to push back the attackers -- who were said mostly to comprise uniformed Libyan troops rather than the foreign mercenaries being deployed by Qaddafi's regime in parts of Tripoli. But Qaddafi's troops had the city surrounded and have been stopping food deliveries from reaching residents.
Libyan Deputy Foreign Minister Khaled Kaim claims Qaddafi's regime was trying to work through tribal and intellectual leaders to stabilize the situation. But Kaim has also threatened more military assaults if opposition leaders refuse to back down from their demands for Qaddafi's resignation.
"If all attempts and efforts for social dialogue and mutual understanding are exhausted, if intellectuals and heads of the tribes and wise people fail in securing stability and peace," Kaim said, "then very well-guided force will be used."
Major Assault
Meanwhile, pro-Qaddafi troops were massing some 10 kilometers further to the west at the town of Nalut near the border with Tunisia. Residents of Nalut said preparations appeared to be under way for another major assault by Qaddafi's troops.
In eastern Libya, under the control of antigovernment demonstrators and defecting army troops since last week, the opposition forces have been enlisting volunteers and training youth to defend against counterattacks by Qaddafi loyalists. As their numbers increase, rank-and-file opposition troops are talking increasingly about an eventual march on Qaddafi's headquarters in Tripoli.
But government troops are fighting back in the east, too. The Libyan Air Force in the last 24 hours bombed an ammunition depot in the city of Dabiya, to the east of Tripoli.
Fighting also has been reported in the opposition-held coastal city of Misurata about 220 kilometers east of Tripoli, with government forces carrying out attacks on a strategic airfield.
The latest violence comes after Qaddafi gave interviews to three Western news outlets -- BBC, ABC, and "The Times" of London -- claiming that the only opposition in the country was foreign Al-Qaeda terrorists and young Libyans on drugs who are taking orders from Al-Qaeda.
Qaddafi laughed when he was asked by one journalist if he would heed growing international calls for his resignation. The embattled ruler said the people of Libya would sacrifice their lives for his regime.
"They love me. All my people [are] with me. They love me all. They will die to protect me, my people," he said.
The U.S. ambassador to the United Nations, Susan Rice, called Qaddafi's statement "delusional."
"When he can laugh in talking to American and international journalists while he is slaughtering his own people," she said, "it only underscores how unfit he is to lead and how disconnected he is from reality."
Rice also said the United States was reaching out to opposition groups in Libya.
In New York, the United Nations voted today to suspend Libya from its Human Rights Council for committing “gross and systematic violations of human rights."
The growing international pressure against Qaddafi's regime also includes weapons and economic sanctions imposed by the United Nations, the European Union, Britain, Germany, Austria and other countries.
Officials from Washington also have been consulting the NATO alliance about the possibility of enforcing a proposed UN resolution that would create a no-fly zone over Libya to prevent Qaddafi's air force from attacking demonstrators with fighter jets and helicopter gunships.
Speaking at a hearing of the House Foreign Affairs Committee on March 1, U.S. Secretary of State Hillary Clinton said the plan was "under active consideration."
She said the Obama administration realizes most Libyans want change to come to their country without foreign interference.
"We are also very conscious of the desire by the Libyan opposition forces that they be seen as doing this by themselves on behalf of the Libyan people, that there not be outside intervention by any external force because they want this have been their accomplishment. We respect that," Clinton said.
At the White House, spokesman Jay Carney said U.S. ships were being moved to waters closer to Libya in order to prepare for contingencies of a chiefly humanitarian nature.
He added, however, that "we aren't taking any options off the table,” and said Qaddafi's inner circle ought to "think twice" about continuing to support him.
Also on March 1, U.S. General James Mattis said enforcing a no-fly zone over the North African country would require eliminating the government’s air defense capabilities first in a "military operation."
But not all world powers are convinced that a no-fly zone is necessary, arguing that most of the force used against the opposition has come through ground assaults.
Russian Foreign Minister Sergei Lavrov said the idea of imposing limits on Libyan air space was "superfluous" and urged world leaders to focus on fully implementing sanctions first.
written by Ron Synovitz and Richard Solash, with agency reports
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