The UK Government will make a swift decision on whether to lift the ban on Islamist group Hayat Tahrir al-Sham (HTS) after it swept to power in Syria, ousting Bashar Assad’s regime.

HTS is banned in the UK because of its past association with al Qaida, the terrorist organisation once led by Osama bin Laden.

Its leader Abu Mohammed al-Golani cut ties with al Qaida years ago and has sought to present his group as a more moderate and inclusive organisation.

Cabinet minister Pat McFadden said “the situation is very fluid” but he hoped if there was a need to hold talks with HTS “it should be a relatively swift decision”.

The rapid collapse of the Assad regime after 13 years of civil war saw a coalition of rebel groups seize Damascus on Sunday, with the former president fleeing to Russia, one of his main allies.

Mr Assad’s British wife Asma is believed to be with him in Moscow.

Mr McFadden, the Chancellor of the Duchy of Lancaster, said a decision on HTS needed to be taken quite quickly.

He told BBC Radio 4’s Today: “They’ve been proscribed for quite a long time now.

We don't know what will happen in Syria right now, whether it's going to be a better future for the country, or whether it's going to be more chaos, no one can be certain about that right now

“The leader of that group has distanced himself away from some of the things that have been said in the past. He is saying some of the right things about the protection of minorities, about respecting people’s rights. So we’ll look at that in the days to come.”

He added: “We don’t know what will happen in Syria right now, whether it’s going to be a better future for the country, or whether it’s going to be more chaos, no one can be certain about that right now.

“But obviously, if the situation stabilises, there’ll be a decision to make about how to deal with whatever new regime is in place there.”

He added: “I think it should be a relatively swift decision so it’s something that will have to be considered quite quickly, given the speed of the situation on the ground.”

Mr McFadden said he was not aware of the UK having any current lines of communication with HTS.

He said there had so far been no request for Mrs Assad to return to the UK.

“The family are in Russia as far as we know, that’s what Russian state media have said.

“We’ve certainly had no contact or no request for Mr Assad’s wife to come to the UK.”

Downing Street said on Monday that the Government keeps the regime of proscribed organisations “under regular review”.

The Prime Minister’s official spokesman said: “When it comes to HTS, they have been proscribed in the UK, having been added as an alias of al Qaida in 2017.

“The Government doesn’t routinely comment in more detail on the list of proscribed organisations, but as you know we keep our regime under regular review.”

The spokesman later said it is “long-standing Government policy we do not engage with proscribed organisations. But, as I say, we keep the regime under regular review, it is an evolving situation”.

The speed of the fall of the Assad regime caught out many international observers after years of bloody civil war between an array of groups and the Syrian military.

The Russian war in Ukraine and Iran’s involvement in conflicts between its proxies and Israel meant two of Mr Assad’s leading backers were preoccupied with their own difficulties, contributing to weakness in the Syrian regime.

Mr McFadden told Sky News: “We know that a brutal regime has fallen, we know this has been bad for Russia and Iran, who were the people propping up that regime and decided that either they wouldn’t or couldn’t prop it up any longer, and the future is very uncertain.”

In a sign of that volatility, Israel struck suspected chemical weapons sites and long-range rockets in Syria in order to prevent them from falling into the hands of “extremists” while the US military carried out air strikes against Islamic State targets in the country on Sunday.