Prime Minister David Cameron has said he is "incredibly sorry" for the government's handling of the evacuation of British nationals from Libya.
Mr Cameron said it had not been an easy situation and ministers needed to "learn the lessons".
His comments followed criticism of a slow government response to the crisis.
The Foreign Office said it had helped a total of 350 British nationals leave Libya on Thursday, including 79 on a flight chartered by oil company BP.
US President Barack Obama and Mr Cameron discussed Libya on the telephone on Thursday night.
'Seizing the moment'
A Downing Street spokesperson said: "The prime minister updated the president on his trip to the Middle East, stressing the importance of seizing this moment of opportunity for change in the region.
"The leaders discussed Libya and agreed to work together closely on the swift evacuation of nationals. They also agreed to co-ordinate on possible multilateral measures on Libya, including at the UN Human Rights Council on Monday."
A flight chartered by the Foreign and Commonwealth Office (FCO), carrying 181 adults and two children, including 113 Britons, landed at Gatwick at 2030 GMT after stopping off in Malta en route from the Libyan capital Tripoli.
One of the Britons from the flight said after arriving back in the UK: "If the government's going to do something it needs to pull its finger out and actually physically do something."
Another said: "The people on the ground from the British embassy, when we finally found them at the airport, they couldn't have been better. But the communication with London, it was just a fiasco."
The FCO said there were up to 220 Britons still stranded in Libya, 50 of them in Tripoli and between 150 and 170 in the more remote oil-producing areas.
Mr Cameron said of the British response: "Of course I am incredibly sorry. They have had a difficult time. The conditions at the airport have been extremely poor.
"There are going to be lessons to be learned from this and we will make absolutely sure that we learn them for the future but, right now, the priority has got to be getting those British nationals home."
The prime minister said there had been "technical faults" with chartered flights.
He added: "We will have a review to check whether it was technical faults or whether there is something systemically wrong.
'Not an easy situation'
"This is not an easy situation to deal with. It is immensely frustrating for the people on the ground and we will do everything we can to get those people home."
Labour leader Ed Miliband criticised the government's reaction to the crisis.
He said: "I'm afraid the government has been slow off the mark and lessons need to be learned, but the priority now is to get those British citizens out as soon as possible. That's why the prime minister needs to get a grip on the situation."
Earlier, shadow foreign secretary Douglas Alexander said the government should have acted sooner to deploy the RAF.
In other developments:
- The oil company flight arrived at Gatwick at about 0715 GMT. The airport said the plane carried 78 adults plus one infant
- A second government-chartered flight arrived in Tripoli on Thursday afternoon, and will return to the UK with at least 50 Britons.
- A third government flight has arrived in Tripoli and will return to the UK overnight. Further planes will be sent as necessary
- An RAF Hercules C130 aircraft arrived in Malta carrying 51 British passengers, 13 other entitled passport holders and a dog, to join the first government charter flight to London. The passengers were met by the British High Commissioner
- The Royal Navy frigate HMS Cumberland has sailed from Libya's second city, Benghazi, with 207 people on board and will arrive at Valetta in Malta on Friday. The FCO said approximately 68 were British
- A second BP-chartered flight was due to land on Thursday evening carrying 26 people, the last of the company's staff in the country
- A second meeting of Cobra, the government's emergency planning committee, has been held, chaired by Foreign Secretary William Hague
- A young British family, including a mother who has just given birth by caesarean section, has left Tripoli aboard an Irish government Lear jet which had a medical emergency team on board.
The British Red Cross has deployed a team of volunteers to Gatwick airport to provide support to Britons being evacuated.
BBC security correspondent Frank Gardner said an SAS contingent has been put on standby for emergency deployment to parts of Libya, backed up by paratroopers of the Special Forces Support Group.
Our correspondent said: "With the situation for some British nationals in Libya fast deteriorating, it's part of a range of options being considered by the government to rescue those stranded in the north African country."
Several other countries, including France, Russia and the Netherlands have already evacuated some of their citizens from Libya.
UK nationals wishing to register an interest in flights out of Libya should call 020 7008 0000 from the UK or 021 3403644/45 from Libya.
The Foreign Office is advising against all but essential travel to Libya.
Around 3,500 Britons had been living in Libya before the crisis but most of those are thought to have left in recent days.
However, there is particular concern for some British oil workers thought to be stranded in isolated desert camps.
They are struggling to make contact because the phone networks have been disrupted and their supplies of food and water from Libyan cities are running out.
"Some we know have been subjected to attacks and looting. They are in a perilous and frightening situation," said Mr Hague.
Tony Blakeway told the BBC he was at a camp in Amal with 300 people, about 50 of them British. He said armed locals had been protecting them but they were worried they would leave.
"Please send immediate help as these looters will be back here tonight. The phones are not working. Please help us to get out," he said.
After a week of upheaval in Libya, protesters backed by defecting army units are thought to have almost the entire eastern half of Libya under their control.
The country's beleaguered leader Col Muammar Gaddafi, who has been in power for 42 years, has vowed to fight to his "last drop of blood" rather than leave the country.
Earlier, Mr Hague told the BBC the "odds were stacking up" against Col Gaddafi, adding: "We have a government, or the remnant of a government, here which is prepared to use force and violence against its own people."
He said the Libyan leadership would be "held to account" for crimes against its people.