Afghanistan's internationally recognised government faces defeat to Taliban forces with supporters living in the capital fearing the "writing is on the wall," according to Dr Ashraf. The regional expert from the University of Nottingham has given a grim appraisal of the current situation in the war-torn country. Taliban forces continue to make rapid advances in the wake of the pullout of western forces and recently announced the capture of another regional capital.

       Dr Afzal Ashraf told Sky News: "I think there will come a time sadly when the writing will be on the wall.

       "And people will decide in Kabul that it is better to give up rather than to fight to what will be a disastrous end for everybody concerned."

       Sky's Alex Rossi pressed the expert: "The way you are talking it is not a question of if, it is just a question of when.

       "It seems there is an air of inevitability that Afghanistan established under the international forces and the United States will fall."

       Dr Ashraf replied: "Yes I think sadly that is correct given the situation as we speak."

       The comments came as Conservative MP Tobias Ellwood has warned the UK's abandonment of Afghanistan could have devastating long-term consequences.

       Mr Ellwood to Express.co.uk earlier this week: "This is really embarrassing for the West.

       “We've lost credibility to uphold and defend democracy when we're leaving after 20 years in this way.”

       The former soldier described the situation in the British-held province of Helmand as "deeply saddening."

       “Not only that, imagine if we had left Germany to its own devices after World War 2," continued Mr Ellwood.

       "Here we are giving this back to the Taliban who no doubt will offer a safe haven to terrorist groups," the MP added.

       "So, mark my words, you're going to see mass migration challenges coming from Afghanistan, humanitarian catastrophes, and rising terrorist attacks."