Details added (first version posted Monday at 22:58)
Opposition fighters made political and military gains Monday, on the eve of a conference in London of the nations participating in the UN-authorized military action in Libya, dpa reported.
British Prime Minister David Cameron and French President Nicolas Sarkozy issued a joint statement urging Moamer Gaddafi's followers to defect and join the rebels before it was "too late."
That message appeared to have already been heeded by at least one group from within the Libyan Army, with a unit of around 10 officers appearing on al-Jazeera TV to announce they were joining the anti- government uprising.
The defection of the army unit comes after more than a week of coalition airstrikes on the Gaddafi's armed forces severely weakened his attempts to regain control of cities now run by the opposition.
A number of military defections over the last six weeks and the handover of munitions and tanks to the rebels have boosted the opposition.
Meanwhile, sources in Sirte and Tripoli told the German Press Agency dpa that Sirte was still under the control of Gaddafi's troops, but rebel forces were 100 kilometres away in the town of Nofiliya.
A senior US officer said late Monday that Gaddafi's regime is reinforcing its positions in Sirte to prepare for a possible rebel assault. Vice Admiral William Gortney, director of the Pentagon's Joint Staff, told reporters that the regime is establishing checkpoints and stationing tanks in Sirte.
"We believe the regime is preparing to dig in at Sirte, setting up a number of checkpoints and placing tanks throughout the city," Gortney said.
He cautioned that the rebels are poorly organized and their advances were "tenuous."
"Clearly, the opposition is not well organized, and it is not a very robust organization," Gortney said. "I mean, that's obvious. So any gain that they make is tenuous, based on that."
The advance on Sitre, Gaddafi's hometown, came after rebels took control of Bin Jawad, Ras Lanuf, the key oil port of al-Burayqa and the town of Uqayla. They are now in control of all oil terminals in the eastern part of the North African country.
After Sirte, which is approximately halfway between the rebel stronghold of Benghazi and Tripoli, the rebels have their sights set on Misurata. Libya's third-largest city, Misurata is seen by the rebels as the gateway to the capital Tripoli.
The opposition's westward move comes on the heels of a NATO decision late Sunday to take over control of all UN-mandated military operations in Libya, including any airstrikes aimed at protecting civilians from Gaddafi's troops.
NATO Secretary General Anders Fogh Rasmussen, who is set to attend the London meeting, hopes that quick progress will be made on the political front, according to a NATO spokeswoman.
"The hope is that we will see a cessation of violence sooner rather than later," said Oana Lungescu. "There is no military solution to the crisis in Libya. There can only be a political solution, and we think the London conference can make a contribution."
The expectation is that the meeting will "provide the broad political lines to ensure there is momentum for a peaceful solution on the ground in Libya," she noted.
Libyan authorities have said that coalition airstrikes over the past week have killed dozens of civilians and members of the military, something which the opposition said was exaggerated to undermine support for the airstrikes.
Libyan opposition sources reported that a coalition airstrike carried out by Britain's Royal Air Force early Monday wounded a number of civilians. That attack on a weapons depot in the south- western city of Jabal al-Sabha caused a number of injuries to civilians and destroyed several homes, said the opposition Libya al- Youm website.
According to the Libyan state-run JANA news agency, children were among the wounded.
On the political front, the opposition made political gains with Qatar becoming the first Arab country to recognize the rebels' National Council as the sole legitimate representative of the Libyan people.
Qatar has pledged to send four fighter jets to the coalition. The Gulf nation follows France, which was the first country to recognize the rebel council.
The Arab League has endorsed the no-fly zone, and both the United Arab Emirates and Jordan have pledged "logistical support" to the mostly Western coalition.
Turkey said it will be taking over the rebel-run Benghazi airport to organize humanitarian assistance in the country as part of the NATO-led multinational task force, the Anatolia Agency reported.
"One is to run the Benghazi airport for the coordination of humanitarian assistance. We will also take part in monitoring the airspace and deploy Turkish naval forces on the corridor between Crete and Benghazi," Turkish Prime Minister Recep Tayyip Erdogan said at a news conference in Ankara.