Boris Johnson has said he will "shift heaven and earth" to get people out of Afghanistan after 31 August as he confirmed British deaths in the "contemptible" attack at Kabul airport.
The British Prime Minister said he felt "a great sense of regret" about those left behind in Afghanistan, as the evacuation process enters its final stages.
Asked about the deaths of two British adults, and a teenager who was a child of a British national, he said: "I think what their loss really underlines is the urgency of getting on and concluding Operation Pitting in the way that we are, and also underlines the bravery of our armed services, our troops, everybody else involved."
Mr Johnson admitted: "Of course, as we come down to the final hours of the operation there will sadly be people who haven't got through, people who might qualify.
"What I would say to them is that we will shift heaven and earth to help them get out, we will do whatever we can in the second phase."
When asked whether the scenes seen in Afghanistan amounted to a national humiliation for the UK, he said: "It's certainly not something that... the timing of this is certainly not the one that this country would have chosen, and I think that everybody understands that."
Earlier, the UK Defence Secretary said Britain's evacuation effort in Kabul has entered its final stages but has not been curtailed by the terror attack that killed US troops and Afghan civilians.
Ben Wallace said this morning there were just "hours" left in the mission to help people flee the Taliban after closing the main processing site, near where the bombs were detonated.
Despite airlifting nearly 14,000 people out of Afghanistan in the past two weeks, Mr Wallace said "the sad fact is not every single one will get out".
He declined to give a timeline for the exit of British forces but acknowledged it would come before the Americans withdraw, with Joe Biden having set a departure date for Tuesday, 31 August.
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Mr Wallace said the Baron Hotel processing centre, near where the bombing took place, was shut at 4.30am, as was the Abbey Gate to Kabul airport.
"We will process the people that we've brought with us, the 1,000 people approximately in the airfield now, and we will seek a way to continue to find a few people in the crowds where we can, but overall the main processing is now closed and we have a matter of hours," he told Sky News.
Mr Wallace said the threat of further attacks around Kabul Airport will increase as Western troops get closer to leaving the country, but denied yesterday's deadly bomb attack had accelerated Britain's departure from Afghanistan.
"The narrative is always going to be certain groups, such as IS, will want to stake a claim that they have driven out the US or the UK.
"We closed the Baron's hotel almost exactly on schedule. The explosion was horrendous, but it didn't hasten our departure," the minister said.
At least 85 people were killed, including 13 US military personnel, after suicide bombers struck the crowded gates of Kabul airport with at least two explosions.
Mr Wallace said one bombing happened in a "standoff area" where British troops had pushed back from the Baron Hotel processing centre.
Italy and Switzerland end evacuation operations
Italy's last evacuation flight from Kabul has left Afghanistan, ending the country's airlift operation, Foreign Minister Luigi Di Maio said.
Mr Di Maio said "that as well as Afghan civilians, the flight will bring back to Italy our envoy Stefano Pontecorvo," the Italian diplomat serving as NATO's senior civil representative to Afghanistan.
The flight, which had "just taken off", is also carrying the last Italian soldiers who were still on site, he tweeted.
Mr Di Maio had told an earlier press conference in Rome with Russian Foreign Minister Sergei Lavrov that the C-130 plane would soon leave Kabul.
He added that all the Italian nationals who wanted to leave had been evacuated, along with around 4,900 Afghan civilians.
Italian consul Tommaso Claudi was on board the last flight as well as Mr Pontecorvo.
"Leaving Kabul with a heavy heart. My gratitude to all #NATO allies & partners for a massive evacuation effort from #Afghanistan despite all challenges," Mr Pontecorvo tweeted.
"NATO played a key role in getting thousands out and is committed to getting others to safety."
Italy has evacuated 4,832 Afghans since June, the defence ministry said in a statement Thursday evening.
Italy was one of the five countries most involved with NATO's "Resolute Support" Mission in Afghanistan, along with the United States, Turkey, Britain and Germany.
The defence ministry said 53 Italian soldiers were killed and 723 wounded out of the 50,000 the country deployed to Afghanistan over the two-decade war.
Meanwhile, the Swiss government said it had ended its evacuation operation out of Kabul after helping airlift 387 people to Switzerland following the Taliban's takeover of Afghanistan.
The foreign ministry said that 34 Swiss nationals were among those evacuated, but that 11 citizens and 16 residents of the wealthy Alpine nation remained in the war-torn country.
Reporting PA, AFP, Reuters
