Abdul Fatah Younis, the head of the Libyan opposition's armed forces, has accused NATO of acting too "slowly", or not acting at all, to protect civilians in their fight against Muammar Gaddafi, the Libyan leader.
Younis' comments came as the rebels were forced out of the oil town of Brega in the country's east by a renewed offensive launched by Gaddafi's forces. The rebels were forced to retreat to Ajdabiya, ending a stalemate over the last five days over who controlled Brega.
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Speaking at a press conference in the opposition stronghold of Benghazi, Younis, who was formerly the country's interior minister, said that NATO had "disappointed" the rebels, even though it is helping them.
"Unfortunately, and I am sorry to say this, NATO has disappointed us. My staff have been in contact with NATO officials to direct them to targets that should protect civilians, but until now, NATO has not given us what we need," he said.
In particular, Younis was scathing in his criticism of the NATO response to events in Misurata, where residents have been under siege from pro-Gaddafi forces for the last 40 days. Younis said that Gaddafi had contaminated the drinking water, and that residents of the city did not have access to basic supplies.
"Civilians are dying daily because of lack of food or milk, even children are dying. Even by bombing. If NATO waits for another week, it will be a crime that NATO will have to carry. What is NATO doing? It is shelling some defined areas only," he said.
"When a large force of tanks, and even artillery, is on its way to Benghazi, Ajdabiya or Brega, we always inform NATO straight away. Because we don't have such weapons. NATO's reaction is very slow. By the time the information reaches from one official to another until it reaches the field commander, it takes hours.
"Will these forces wait for hours to bomb? No, they will go into the city and burn it down. That is why I want NATO to stand with us and support us, otherwise I will ask the [opposition] National Council to address this issue at the UN Security Council."
Younis said that rebel forces were providing NATO with the coordinates where pro-Gaddafi forces were present, but they were slow to act, allowing the forces to "enter a city, kill everybody, burn it down and then leave the city" before any action was taken.
He also complained that NATO was not allowing the opposition to use the MiG fighter aircraft and helicopters that it had repaired.
"NATO is moving very slowly, allowing Gaddafi forces to advance ... NATO has become our problem," he said.
Earlier in the day, Brigadier General Mark van Uhm, NATO's chief of allied operations, said that NATO's new "number one priority" was the western town of Misurata, which Younis said was being inadequately protected.
"Misurata is a number one priority because of the situation on the ground over there. We have confirmation that in Misurata tanks are being dispersed, being hidden, [and] humans being used as shields in order to prevent NATO sorties to identify targets," he said.
Van Uhm said that Gaddafi's troops have been adjusting their tactics to deal with the threat from coalition airstrikes, travelling in trucks and light vehicles to the front line and hiding their tanks and armoured vehicles from sight.
He said NATO had so far taken out 30 per cent of Gaddafi's military power, and had struck targets near Misurata on Monday.
Brega falls to Gaddafi forces
Earlier on Tuesday, Libyan rebel forces abandoned the oil town of Brega and headed east toward Ajdabiya in the face of a renewed offensive by troops loyal to Muammar Gaddafi.
Both sides exchanged heavy fire on Tuesday, but just a day after rebels had taken over a residential part of the city, they were forced to retreat.
Opposition forces said they came under rocket and artillery fire while they attempted to fight back with mortars and rockets of their own.
"When you see this, the situation is very bad. We cannot match their weapons,'' said Kamal Mughrabi, 64, a retired soldier who joined the opposition army. "If the [coalition] planes don't come back and hit them we'll have to keep pulling back."
Early in the day, a coalition airstrike targeted eight government vehicles that were advancing on opposition positions, rebel officer Abdel-Basset Abibi said.
Al Jazeera's Hoda Abdel-Hamid, in Ajdabiya, reported that opposition forces had been pushed back 20-30km east of Brega towards Ajdabiya by the Gaddafi forces' mid-morning offensive.
"Since this morning we were trying to get as close as possible to Brega. We reached the junction on the road that would lead inside that town, but since mid-morning, opposition forces have been coming under a rolling artillery and mortar barrage," she reported.
Rebel oil export
Meanwhile, the rebels plan to load their first oil shipments on Tuesday.
The tanker Equator, which can carry a million barrels of crude, was due to arrive at the eastern port of Marsa el Hariga, near Tobruk, satellite ship tracking data showed even as a Suezmax tanker docked at the port of Tobruk.
A full load of oil on either tanker would be worth millions of dollars, helping the rebel leadership to pay salaries and bolster its image as a potential government capable of taking over.
The last oil shipment to leave Libya was on March 18.
It is unclear at the moment who is buying the oil, though the Suezmax tanker is flying under a Liberian flag, and theEquator is operated by a Greek company.
The frontline in the conflict has been bogged down around Brega for nearly a week, with Gaddafi's advantage in tanks and artillery cancelled out by NATO-led air strikes which effectively back the rebels.
After a series of rapid rebel advances followed by headlong retreats, the pro-democracy fighters had at least held their ground in this oil town for several days, putting their best trained forces into battle for the town and keeping disorganised volunteers away.
Abibi, the rebel officer, said the two sides battled inside the city until nightfall on Monday and then the rebels moved back to the outskirts. The night passed without much incident, until the coalition airstrike on Tuesday morning.
Tuesday's Gaddafi offensive, however, broke the pattern.
"Over the past few days it actually seemed as if the opposition forces were able to hold some sort of position around the town of Brega. Well, today the situation was completely different. The Gaddafi forces were much more aggresive than they had been in the past days, it seem that maybe they had received new supplies, but certainly they have been pounding much more intensely than over the past few days," our correspondent said.
Mustafa Gheirani, a spokesman for the opposition's Transition National Council in Benghazi, said that while "setbacks" had been suffered, the opposition would fight on.
"There is no revolution without setbacks. But the people will win. Gaddafi cannot rule Libya with his machine - his militias and his mercenaries ... We are committed to fighting this tyrant, and either we will drive him out or he will rule a country with no people in it," he said.
Christopher Stevens, the former deputy chief of the US mission in Tripoli, has now arrived in Benghazi to hold talks with members of the opposition's TNC. The US has not formally recognised the TNC as Libya's legitimate government, as several other countries have, and Stevens is in the country to "get to know [its] members", a US official told Reuters.
On Tuesday, Geoff Morrell, the Pentagon's spokesman, said the US was still undecided on whether or not to help arm the rebels, but would be discussing providing "non-lethal" assistance in the coming days.
General Carter Hamm, the US general in charge of Africa Command, under whom US military operations in Libya fell, also testified before US lawmakers in Washington DC.
He reiterated that the US had handed over full command of the mission to NATO, and that US forces would only now act in a supporting role.
Meanwhile, the Libyan government appointed Abdelati Obeidi as the country's foreign minister, replacing Moussa Koussa, who fled Libya for the UK.