The “vast bulk” of British citizens in Afghanistan will be brought back to the UK over the “next few days”, Boris Johnson has said.

Efforts will also be stepped up to relocate Afghans to the UK who have assisted the military operation over the past 20 years, the prime minister said.

The prime minister spoke after chairing an emergency Cobra meeting this afternoon over the deteriorating security situation in Afghanistan, with the Taliban making rapid gains.

“In the course of the next few days we will see the vast bulk of UK embassy staff, officials, come back, and step up our efforts to bring back those Afghans who have helped us, the UK, international forces, throughout the last 20 years,” said the prime minister.

“To help them, we’re sending out another team of Home Office officials to help them with their applications and get them out.”

He added: “We are appealing to those who have association with the UK who want to come out now to come forward and identify themselves.”

Amid condemnation from some quarters about the US and UK’s decision to withdraw, Mr Johnson said it was a “very difficult” situation but defended the move.

“The UK can be extremely proud of what has been done in Afghanistan over the last 20 years,” he said.

He added: “Thanks to the efforts of the UK armed services, all the sacrifices they made, we have seen no al Qaeda attacks against the West for a very long time… and there are millions of girls and young women who have been educated in Afghanistan.”

It comes after the government announced on Thursday that it would deploy 600 UK troops to Afghanistan to help evacuate Britons.

Earlier today, Taliban fighters took control of the Afghan city of Lashkar Gah, following their capture of Kandahar and Herat.

US intelligence has warned that Kabul, the capital, could fall within 90 days.