The Air forces, still mostly made up of US jets I am given to understand, seems to be taking on the role of referee, blowing up government armored forces that fire on civilians or population centers and not intervening in combat between armed forces. I could be wrong about this but I have heard reports that NATO jets don't engage government tanks if they aren't firing on civilians.Libyan rebels are battling for control of the road leading to the heartland of government loyalists.
The rebel army has been moving rapidly westwards, but came under heavy attack on the approach to Col Muammar Gaddafi's birthplace of Sirte.
Nato, which now runs the coalition action, has denied its strikes are to provide cover for a rebel advance.
Britain and France have urged Col Gaddafi's supporters to defect "before it is too late".
The anti-Gaddafi rebels have seized a number of key coastal communities and important oil installations in recent days, including Ras Lanuf, Brega, Uqayla and Bin Jawad.
Earlier on Monday, the rebels said they had seized Sirte, but the BBC's Ben Brown in rebel-held Bin Jawad says it is now clear their progress was halted before they reached Sirte.
They came under repeated ambush from government troops, says our correspondent.
In facts: Sirte
* Birthplace of Libyan leader Muammar Gaddafi
* Port city 450km (280 miles) east of Libya's capital Tripoli
* Halfway along Libya's northern coast between Tripoli and rebel stronghold of Benghazi
* Home to some ministerial offices as Col Gaddafi tried to transfer more authority
* Population of around 140,000
* Libya: The turning of the tide
* Col Gaddafi's hometown of Sirte
Reports said bombardments of the road between Bin Jawad and Nawfaliyah sent the rebels fleeing back towards Bin Jawad.
"This is the front line. The army has stopped over there, we are stopping here," one fighter told Reuters, indicating the road towards the town of Nawfaliyah.
AFP news agency says the shells fired at the poorly armed rebel convoy landed mostly on sand dunes.
"It won't be as easy as we thought to take Sirte and then march on [the capital] Tripoli," one rebel told the news agency.
"But we won't stop - we'll advance. They can't hold us up for long."
AFP said the rebels had again begun to move cautiously towards Sirte, which is about halfway along the coast between Tripoli and Benghazi.
Nato command
On Sunday, Nato began taking over control of the coalition military action in Libya.
The mission had previously been under US command, with the alliance responsible for enforcing the no-fly zone and arms embargo.
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Analysis
image of John Simpson John Simpson World Affairs Editor, Tripoli
As Gaddafi's hometown, Sirte has a great deal of support for the leader. We're told there have been signs of discontent and perhaps a split among Gaddafi's people there, but nevertheless its importance is that it's the only major place in the centre of the country still held by Gaddafi forces.
They've lost the whole of the east and if they lose Sirte they would have lost the middle of the country as well. The rebels would feel their progress towards Tripoli was unstoppable.
Although seemingly premature, I suspect the reports of rebels taking the city are having a psychological impact on Gaddafi supporters in Tripoli.
Three weeks ago it was obvious that the morale of the Gaddafi forces wasn't terribly high and now, combined with the attacks of the coalition forces, it must be worse.
The quicker the rebel progress goes, the faster morale here will start to buckle. But if progress slows I suspect the reverse may happen, and resistance will stiffen.
The head of the Nato operation, Canada's Lt Gen Charles Bouchard, has rejected suggestions that the coalition air strikes were to provide cover for the rebels to advance.
"Our goal is to protect and help the civilians and population centres under the threat of attack," he told a news conference.
Lt Gen Bouchard said the alliance was taking steps to ensure "minimum collateral damage".
"Our job is to ensure the safety of people and we will do what it takes to do that, but we will also ensure that we ensure their safety in doing our operation," he said.
Coalition strikes on government military bases are continuing - Britain's Ministry of Defence said its aircraft destroyed ammunition bunkers on Monday morning in the Sabha region, in the southern desert.
France said its jets struck a Gaddafi command centre 10km (six miles) south of Tripoli's suburbs on Sunday night.
Russian Foreign Minister Sergei Lavrov has criticised the military action, saying it goes beyond the remit of the UN Security Council resolution and amounted to interference in a "civil war".
The battle for Misrata, the last significant rebel-held city in western Libya, has continued, with Gaddafi forces reportedly shelling the city on Monday.
But later in the day, the foreign ministry said a ceasefire was in place and that calm had been restored.
"The city of Misrata now enjoys security and tranquillity and public services have started to recover their ability to provide customary services to all citizens," the state news agency Jana quoted officials as saying.
Britain and France have issued a joint statement calling on Col Gaddafi's supporters to "leave him before it is too late".
"We call on all Libyans who believe that Gaddafi is leading Libya into a disaster to take the initiative now to organise a transition process," they said.
The countries said this process could involve the rebels' "pioneering" Transitional National Council in Benghazi and "civil society leaders as well as all those prepared to join the process of transition to democracy".
"We encourage them to begin a national political dialogue, leading to a representative process of transition, constitutional reform and preparation for free and fair elections."
Meanwhile, Qatar has become the first Arab nation to recognise the rebel council as the official representatives of the Libyan people.
This frankly will mean a longer fight. Gaddafi cannot use his artillery and tank advantage for a quick win without bombarding cities as the rebels retreat into them. He doesn't really have the manpower to clear those cities house by house. Meanwhile the rebels don't have the organization or training to really win open field battles.
On the flip side the only real way to force a quick decision will be land troops and none of us want that. I don't want it because frankly the US doesn't have the troops, time or money to spare for major ground operations in yet another country. The Euros frankly don't want to embark on major operations if there aren't going to be a crapload of US troops around.