Britain's Defense Secretary Ben Wallace said Tuesday it is "unlikely" evacuations from Afghanistan will be extended beyond August 31 as Group of Seven (G7) leaders prepare to meet virtually to discuss the crisis. 

The UK will chair the emergency talks among G7 leaders later on Tuesday, at which U.S. President Joe Biden will face pressure to extend the end-of-month deadline to evacuate thousands seeking to leave Afghanistan. 

The Taliban have said they will reject any demands by Western forces to extend the deadline to allow more time to complete the evacuation operation. 

Biden said on Sunday that he would not like to extend the deadline for evacuations, but the talks were ongoing. 

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Wallace told Sky News he was doubtful there would be an extension "not only because of what the Taliban said but also if you look at the public statements of President Biden." 

But he added, "It is definitely worth us all trying, and we will." 

Wallace said if Western forces do not leave by the deadline the Taliban could attack the airport or prevent people from arriving. 

"If that airport gets attacked then effectively it closes down, mortar fire onto the runway etc, and then you are left with a very big humanitarian problem," he said. 

Britain has evacuated around 8,600 people from Afghanistan in last two weeks, including 2,000 people in the last 24 hours, Wallace said.  

But he said given the limited time before the evacuation window closes, "we're not going to get everybody out."

Meanwhile, France said it will end its evacuation missions in Afghans later this week if the U.S. presses on with its plan to pull all troops out of the country at the end of the month. 

"For us ... that means that our operation ends Thursday evening. So we have three days left," Nicolas Roche, the chief of staff for Foreign Minister Jean-Yves Le Drian, told French Prime Minister Jean Castex. 

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Conflicts between Taliban fighters and Western-backed government forces escalated after U.S.-led foreign troops began the final stage of their withdrawal from Afghanistan in May. As the Taliban took control of Kabul on August 15, the U.S. and some other countries intensified efforts to evacuate their diplomats and other nationals as well as Afghans who want to leave the country. 

A Taliban spokesman warned on Monday that the group would not agree to any extension of the August 31 deadline, calling it a "red line" for withdrawing troops. 

"If the U.S. or UK were to seek additional time to continue evacuations – the answer is no. Or there would be consequences," Taliban spokesman Suhail Shaheen told Sky News. 

In an interview with CGTN on Monday, Shaheen said any delay in the full withdrawal of U.S. troops from Afghanistan "would be a clear violation" of the departure agreement. 

(With input from AFP, Reuters)

(Cover: Afghans board a U.S. Air Force Boeing C-17 Globemaster III during an evacuation at Hamid Karzai International Airport, Kabul, Afghanistan, August 23, 2021. /CFP)