Foreign Minister Dominic Raab said the intelligence assessment was that Kabul would not fall this year as he defended Britain’s exit from Afghanistan as the Taliban swept the country considerably more quickly.

The UK, like the US, underestimated how quickly the Afghan government would fall, suggesting that it had not sufficiently prepared for the chaos that would come after the Taliban gained power.

Raab said the central assessment of Britain’s intelligence service was that the Taliban would only consolidate control of the country in the months after western countries had evacuated their troops in an emergency session of parliament’s foreign affairs committee to discuss the crisis in Afghanistan.

“The fundamental notion was that, given the military departure by the end of August, you would witness a gradual deterioration from that point forward, and that Kabul would be unlikely to fall this year,” Raab told the MPs’ committee.

“That doesn’t mean we didn’t do contingency planning or game-out or test the other propositions. And just to be clear, that’s something that was widely shared – that view – amongst NATO allies.”

Prime Minister Boris Johnson has faced calls to sack Raab in recent weeks after he went on holiday in Crete as the Taliban advanced on Kabul and amid claims that thousands of emails from people seeking help to leave Afghanistan had gone unread.

Defending his handling of the crisis, Raab said he had had more than 40 meetings or calls where Afghanistan was on the agenda between March and end of August.

Britain’s last military flight left Kabul late on Saturday, ending a chaotic two weeks in which soldiers helped to evacuate more than 15,000 people from the crowds who descended on the capital’s airport, desperate to flee the country.

Raab said he would travel to the region, including visiting Pakistan for the first time as foreign minister, later on Wednesday to discuss the crisis.