Libya's rebels on Monday denied reports they were talking with the tottering regime of Moammar Gadhafi, as fighting raged in both east and west and Washington said the strongman's "days are numbered."

The United Nations also denied that its special envoy on Libya Abdul Ilah al-Khatib was involved with talks in Tunisia between representatives of Gadhafi and the rebels after Khatib had indicated he would be joining such talks.

U.N. Secretary General Ban Ki-Moon's envoy on Libya flew into Tunis Monday, saying he would be joining talks between rebels and the government of embattled leader Moammar Gadhafi.

Former Jordanian foreign minister Abdul Ilah al-Khatib said negotiations on Libya's future would be taking place in a hotel in the Tunis suburbs.

Libyan leader Moammar Gadhafi spat defiance at opposition forces and NATO on Monday amid rumors he was preparing to flee the country and as rebels made advances in several towns, especially in the west.

The veteran leader predicted a swift end for "the rats" and the "colonizer", referring to the rebels and NATO, in an audio message on Libyan television, extracts of which were published by Libyan news agency JANA.

Some 2,000 migrants from north Africa have arrived on the southern Italian island of Lampedusa this weekend, ANSA news agency reported Sunday.

About 100 women and 40 children including three babies were among those who reached the island between Saturday morning and Sunday morning on a dozen boats.

Six months after the start of the conflict in Libya, NATO believes that the resistance of Moammar Gadhafi's regime can be overcome and rebels finally get the upper hand.

U.N. Security Council Resolution 1973 authorized the Atlantic Alliance in March to defend Libya's civilian population from attacks by Gadhafi’s regime, which faces a popular revolt after 42 years in power.

Rebels fighting east of Tripoli said they strengthened their grip on the town of Tuarga on Saturday, in a bid to create a buffer zone between Moammar Gadhafi's forces and the city of Misrata.

On the third day of an offensive, rebels from the port enclave of Misrata said they routed all but the last remaining pockets of resistance from loyalist forces.

The Libyan government insisted Zawiyah was under the regime's control on Saturday, dismissing rebel claims of having captured the port city on the road to Tripoli.

Zawiyah is completely under government control, government spokesman Moussa Ibrahim told reporters in the capital.

An imprisoned Libyan army colonel who surrendered to the rebel forces two months ago told Agence France Presse on Saturday that Moammar Gadhafi's regime is ridden with divisions and in the process of collapse.

Speaking from a prisoner of war camp in the rebel enclave of Misrata, Colonel Wissam Miland said Gadhafi's military hangs together through coercion and mercenary-enforced martial law, but that infighting is rife.

Oil prices fell below $85 a barrel Friday in Asia as investors tried to make sense of a week of sharp zigzags in the equity and commodities markets.

Benchmark oil for September delivery was down $1.08 to $84.64 a barrel at late afternoon Singapore time in electronic trading on the New York Mercantile Exchange. Crude rose $2.83, or 3.4 percent, to settle at $85.72 on Thursday.

U.N. leader Ban Ki-moon on Thursday expressed alarm over the rising number of civilian casualties in the Libya conflict, including those inflicted in NATO airstrikes.

Without specifically naming any side, Ban called on "all parties" to use "extreme caution" in the battle, said a U.N. statement. Ban also stepped up calls for a political solution to the conflict, in which rebels have sought to overthrow Moammar Gadhafi's four-decades-old regime.