Jens Stoltenberg warned Tuesday that NATO could pay a heavy price for leaving Afghanistan too early. His comments come after US President Donald Trump vowed to significantly reduce the number of US troops in the war-ravaged country by January 2021.

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"We now face a difficult decision," Stoltenberg said in a statement. "We have been in Afghanistan for almost 20 years, and no NATO ally wants to stay any longer than necessary. But at the same time, the price for leaving too soon or in an uncoordinated way could be very high,'' he added.

NATO has around 12,000 international troops in Afghanistan which are tasked with helping to train and advise the country's national security forces. Over half of these troops are not from the US, but the 30-nation alliance relies heavily on the US for transport, air support, logistics and other assistance. It's unlikely that NATO could continue its operation in Afghanistan without the US help.

The NATO chief added that Afghanistan still "risks becoming once again a platform for international terrorists to plan and organize attacks on our homelands. And ISIS (the "Islamic State" militia) could rebuild in Afghanistan the terror caliphate it lost in Syria and Iraq."

NATO took charge of the international security effort in Afghanistan in 2003, two years after a US-led coalition invaded the country and dismantled the Taliban regime.

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NATO 'should leave together'

Newly appointed Pentagon chief Christopher Miller on Saturday signaled that he might accelerate the withdrawal of US forces from Afghanistan and Iraq, in line with President Trump's pledge to end US involvement in foreign wars.

"We met the challenge; we gave it our all. Now, it's time to come home," the acting defense secretary said in his first remarks to the US armed forces.

But Stoltenberg says that "even with further US reductions, NATO will continue its mission to train, advise and assist the Afghan security forces," adding that the alliance was also "committed to funding them through 2024."

Read more: Afghanistan troop withdrawal: NATO staying as long as necessary

"Hundreds of thousands of troops from Europe and beyond have stood shoulder to shoulder with American troops in Afghanistan, and over 1,000 of them have paid the ultimate price," Stoltenberg said.

"We went into Afghanistan together. And when the time is right, we should leave together in a coordinated and orderly way. I count on all NATO allies to live up to this commitment, for our own security," he said.

Conditions on the ground

German Defense Minister Annegret Kramp-Karrenbauer said Tuesday that any decisions on the withdrawal of troops from Afghanistan must be based on conditions on the ground.

"The ongoing peace negotiations in Afghanistan have not yet brought the results that we all wish for," Kramp-Karrenbauer said.

"We have agreed in NATO, together with the US, that any reduction of troops or a complete withdrawal must be based on conditions to be defined reliably in a peace treaty," the German defense minister added.

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After several rounds of difficult talks, the US and the Taliban in February signed a deal in Doha, Qatar, which has paved the way for the withdrawal of US troops from Afghanistan. 

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The Afghan government and Taliban representatives are currently holding intra-Afghan talks in Doha. One of Kabul's demands is that the Taliban agree to a nationwide cease-fire to facilitate peace negotiations. Violence in Afghanistan, however, has escalated in the past few months.

shs/dj  (Reuters, AFP)