“She has been sanctioned by the government for a reason – the Assad family were responsible for some of the worst atrocities in modern times.”

Foreign Secretary David Lammy said Asma al-Assad was “not welcome” back in Britain, adding there were still sanctions in place against her, the Telegraph reported.

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On Monday, the UN organisation assisting in investigating the most serious crimes in Syria said the country’s new authorities were “very receptive” to its request for co-operation during a just-concluded visit to Damascus, and it was preparing to deploy.

The visit, led by Robert Petit, head of the International, Impartial and Independent Mechanism for Syria, was the first since the organisation was established by the UN General Assembly in 2016. It was created to assist in evidence-gathering and prosecution of individuals responsible for possible war crimes, crimes against humanity and genocide since Syria’s civil war began in 2011.

An international war crimes prosecutor said evidence emerging from mass grave sites in Syria had exposed a state-run “machinery of death” under the Assad regime, in which he estimated more than 100,000 people had been tortured and murdered since 2013.

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Assad presided over the deaths of an estimated 400,000 Syrians during the 13-year civil war, many killed by air strikes and the use of poison gas. Russia helped supply the air power for the missions as well.

Petit highlighted the urgency of preserving documents and other evidence before it is lost.

Since the rebel overthrow of Assad and the opening of prisons and detention facilities, there have been rising demands from Syrians for those responsible for atrocities and killings to be prosecuted.

“The fall of the Assad rule is a significant opportunity for us to fulfil our mandate on the ground,” Petit said. “Time is running out. There is a small window of opportunity to secure these sites and the material they hold.”

UN associate spokesperson Stephanie Tremblay said on Monday that the investigative team was “preparing for deployment as early as possible and as soon as it is authorised to conduct activities on Syrian soil”.

Reuters, AP with Chris Zappone

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