KABUL — The lightning sweep across Afghanistan by the Taliban has caused a mixture of dismay, consternation and anger among leading politicians and military figures in Europe and the West.

Much of the wrath has been directed at the American and British governments over troop withdrawals, seen as a betrayal of the Afghan people.

The militants have made their biggest gains yet over the past two days, capturing several major cities especially in the south of the country, just weeks before the US plans to withdraw its last troops.

Thousands of Afghans have fled their homes in recent weeks amid fears the Taliban will again impose a brutal, repressive government in the name of Sharia law, all but eliminating women’s rights and conducting public executions.

The troop withdrawals — 20 years after the US-led invasion which ousted the Taliban from power, had sparked fears of a militant resurgence. But the speed of their advance, and the collapse of Afghan government resistance in many areas, has surprised observers.

When President Biden announced the final US pullout in April, NATO also agreed to withdraw its roughly 7,000 non-American forces from Afghanistan, while still pledging support for the country.

Most EU countries contributed troops to the NATO force. By the end of June, those with the highest numbers — Germany, Italy and Poland — had declared their missions over.

The UK's Defense Secretary Ben Wallace said on Friday he was worried that Al-Qaeda — once sheltered by the Taliban — would return to Afghanistan. He admitted that the withdrawal of US and British forces posed a lot of strategic problems, and agreed there was a risk of a renewed security risk to Western populations.

"Failed states breed poverty, and failed states breed security challenges, domestically inside those countries and also to the international community," he told the BBC.

Wallace added that he had previously criticized the 2020 deal struck by the Trump Administration with the Taliban as "not the right thing", but defended the British troop withdrawal as "the solution has to be international" for Afghanistan.

UK Prime Minister Boris Johnson was to chair a meeting of the government's emergency COBRA crisis unit on Friday afternoon to discuss Afghanistan.

Other leading figures in Britain's ruling Conservative Party were stronger in their condemnation, including of their own government, over the pullout.

Former military veterans minister Johnny Mercer — who served as a soldier in Afghanistan — said the UK had "chosen defeat", describing the lack of "political will" as "shameful,", "sad," "humiliating for the British army," and above all a "tragedy for the Afghan people".

The chairman of the parliamentary Foreign Affairs Committee, Tom Tugendhat, said the decision to withdraw even air support or maintenance crews was "like a rug pulled from under the feet of our partners" in Afghanistan.

"That means battle winning technology we had taught the Afghans to rely on is useless. Billions of dollars of assets, wasted. Instead of a sustainable peace, incrementally building, we’re seeing a rout," he tweeted.

Rory Stewart, a minister in the last Tory government under Theresa May, said the UK would have to deal with the humanitarian crisis resulting from the Taliban's resurgence.

"There are going to be millions of Afghans in horrifying conditions. It's going to be heartbreaking. There'll be millions of refugees," he told Sky News. "This is our fault," he added.

London and Washington are both sending troops back to Kabul to secure the exit of British and American nationals from Afghanistan in the face of the Taliban advance.

Former UK chief of defense staff Lord Richards said he was "almost ashamed", describing the move as "a gross, dismal failure of geostrategy and of statecraft... an admission of failure and a desire to pull people out."

On Friday, EU governments also concentrated their practical efforts on helping their own countries' nationals leave Afghanistan. Germany and Denmark were among those setting out plans to wind down embassies and get staff out.

German Foreign Minister Heiko Mass said a “crisis support team” was being sent to Kabul where the diplomatic operation would be cut to the "absolute minimum".

The EU's top diplomat Josep Borrell concentrated his criticism on the Taliban for their human rights violations, calling for an immediate halt to the violence that was causing "unacceptable suffering to Afghan citizens". The Taliban would face international "isolation" if "power is taken by force", he said in a Thursday night statement.

Speaking in May as EU ministers met following the US withdrawal announcement, Borrell said "it’s clear that once the US will withdraw, the European Union troops will not be able to stay," calling for Europe to “take positive decisions in order to face reality."

"It is all the more important for the EU to make very clear that Afghanistan and the Afghan government can continue to count on Europe’s support," Heiko Mass said at the time, citing "the terrible attacks of recent days".

But across the Atlantic, there has also been fierce criticism of the US troop withdrawal — including among Republicans, even though the pullout was signaled by Donald Trump when he was in the White House.

"Afghanistan is careening toward a massive, predictable, and preventable disaster," Senate Minority leader Mitch McConnell said in a statement. Condemning "President Biden's reckless policy", he said there was a risk of "an even worse sequel to the humiliating fall of Saigon in 1975" at the end of the Vietnam War.

But Bill Roggio, a senior fellow at the right-wing Foundation for Defense of Democracies, blamed the Afghan army which he said was rotten, corrupt and mismanaged. "Whatever forces are left or remaining that are in the Kabul area and the provinces around them, they’re going to be used for the defense of Kabul," he said.

Such arguments are contested by Paul D. Miller, former Director for Afghanistan on the US National Security Council under Presidents George W. Bush and Barack Obama. In a Twitter thread he dismisses "myths" such as that the US presence was unsustainable or doomed to failure.

"You underestimate the morale-crippling effects of the US rapid withdrawal. Till now Afghans could reasonably bank on a future w/ our help. No more. That explains the collapse," he tweeted.

Echoing Trump, President Biden has also said he is determined to end America's longest war. Announcing the timeline for the US withdrawal in April, he said all remaining troops would pull out by Sept. 11, the 20th anniversary of the Al Qaeda terrorist attacks on New York and Washington.

At the end of June, the top US commander in Afghanistan General Austin S. Miller warned of the danger of civil war, citing the rapid loss of districts around the country to the Taliban.

Weeks before the deadline for withdrawal, the Taliban now control more than two-thirds of Afghanistan and over half of its provincial capitals, including the second and third-largest cities of Kandahar and Herat. The capital Kabul is not yet under direct threat, but there are fears it too could fall.

The onslaught represents a stunning collapse of Afghan forces and renews questions about $830 billion (€705.3 billion) spent by the US Defense Department on fighting, training, and reconstruction. — Euronews with inputs from agencies