The Taliban is unlikely to have changed since it was last in power in Afghanistan 20 years ago, retired senior military and diplomatic figures have said.

The group, which seized Kabul a fortnight ago, has been at pains to stress that its attitudes towards issues such as women being allowed to go to work and violence had shifted.

But the UK’s former ambassador to Afghanistan and a former head of the British Army both said they did not believe this was the case.

Speaking to Times Radio, Sir Nicholas Kay, who was the ambassador to Afghanistan from 2017 to 2019, said the UK does not need to trust the Taliban.

He said: “I first met the Taliban back in early ’95, just after they captured Kandahar when they first appeared on the scene. And I met them in ’96 in Kabul about three days after they’ve captured Kabul, and I’ve been sort of tracking their progress one way or another over the last 20 years.

“I don’t think they’ve changed. You know, I think you know, one of their strengths, if you like, is their single-mindedness and their strength of conviction and their faith in what they are doing and their cause.

“What we have seen is that they are more aware of what they should be saying, and maybe that will translate into being able to actually do some of the things that they’re saying.”

But he added the UK would have to engage with the Taliban, and said: “We do need to engage with them, we don’t need to trust them, we need to test them.”

Earlier, General Lord Richard Dannatt, who was chief of the general staff from 2006 to 2009, told the radio station: “I’m not optimistic that we’re going to see a very different Taliban over time than that which we saw 20 years ago.”

Government ministers have been insistent that the Taliban will be judged on its actions rather than words.

But former veterans minister Johnny Mercer, who fought in Afghanistan, wrote in the Sunday Times that they were “the same rag-tag collection of gangsters, criminals and paedophiles with no regard for human life I fought against just 10 years ago”.

Prime Minister Boris Johnson said: “Together with our allies in America and Europe and around the world, we will engage with the Taliban, not on the basis of what they say but what they do.

“If the new regime in Kabul wants diplomatic recognition, or to unlock the billions that are currently frozen, they will have to ensure safe passage for those who wish to leave the country, to respect the rights of women and girls, to prevent Afghanistan from, again, becoming an incubator for global terror, because that would be disastrous for Afghanistan.”