Britain on Thursday warned that there was a 'very credible' report of an 'imminent' terrorist attack by the Islamic State terrorists targeting those gathering at Kabul airport in an attempt to flee war-torn Afghanistan.
United States President Joe Biden had also mentioned the growing risk of an attack by the ISIS-K, an ISIS affiliate in Afghanistan, when he announced his decision earlier this week not to extend the August 31 deadline for US-led NATO troops to leave Afghanistan after the Taliban takeover.
There is 'very, very credible' intelligence that Islamic State terrorists are planning an imminent attack on those gathering at Kabul airport in an attempt to flee Afghanistan, British armed forces minister James Heappey told BBC on Thursday.
The Foreign, Commonwealth and Development Office (FCDO) said on Wednesday that the situation in the region remains 'volatile', with the advice being for British citizens and other evacuees to find a safe location and await further advice.
The development is related to threats of an Islamic State (ISIS) Afghanistan affiliate, dubbed Islamic State Khorasan or ISIS-K, which is known for conducting suicide bombings and car bomb attacks.
'The security situation in Afghanistan remains volatile. There is an ongoing and high threat of terrorist attack,' the FCDO's updated travel advisory reads.
'Do not travel to Kabul Hamid Karzai International Airport. If you are in the area of the airport, move away to a safe location and await further advice,' it says.
Kabul airport is currently being defended and run by the US, which has 5,800 troops on the ground. However, they are dependent on Taliban support which leaves the international troops vulnerable.
On Thursday, Australia's Minister for Foreign Affairs, Marise Payne, said: "There is an ongoing and very high threat of a terrorist attack."
The US has also asked its citizens in Afghanistan not to travel or gather at the Kabul airport 'because of security threats outside the gates'.
The UK government said its operation to remove British nationals, as well as Afghans who worked for the UK and other vulnerable individuals, is moving at a 'significant pace'.
According to the Ministry of Defence, more than 11,000 people have been evacuated with the help of 1,000 UK troops since August 13 when the Taliban advance was mounted.
The total also includes British embassy staff, British nationals, those eligible under the UK government's relocation programme -- Afghan Relocation and Assistance Policy (ARAP) -- and some evacuees from allied countries.
On Wednesday, UK Foreign Secretary Dominic Raab said that about 2,000 people have been airlifted back to the UK in the last 24 hours and that 'the system is operating at full speed'.
"We will use every last remaining hour and day to get everyone we can back, the British nationals, the Afghans who worked so loyally for us, we are getting the Chevening scholars back, also women's rights defenders and journalists," he said.
UK Defence Secretary Ben Wallace told members of Parliament that some Afghans wanting to flee to Britain may be better off trying to reach one of the country's borders and making their way to a third country.
Over 82,000 people have been airlifted from Kabul after the Taliban seized power in Afghanistan on August 15, two weeks before the US was set to complete its troop withdrawal after a costly two-decade war.
Thousands of people are still waiting inside and outside the airport, hoping to fly out of the country.