Sanctions imposed on the British-born wife of former Syrian president, Bashar al-Assad, would prevent her from being able to return to the UK.
Reports at the weekend suggested Asma al-Assad was planning to divorce her husband and leave Russia where the family is currently in exile.
But the Government indicated that tough sanctions already on the Assads, including a travel ban and asset freeze on the wife of the former president, would stop her returning to the UK.
Downing Street would not be drawn on whether her citizenship could be revoked.
The i Paper reported earlier this month that British laws allow the Home Secretary to revoke an individual’s citizenship if they are satisfied that such a move would be “conducive to the public good”.
But No 10 pointed to remarks by Foreign Secretary David Lammy, who told the Commons earlier this month Mrs Assad “is a sanctioned individual and is not welcome here in the UK”.
Asked whether she could have her citizenship revoked to stop her coming to the UK, a No 10 spokesman said: “I think we have always said that we don’t comment on individuals in relation to this.
“But more broadly you will have seen that we have very tough sanctions in place against the Assad family and the former regime, which remain in place.”
The spokesman confirmed that Lammy’s statement meant the sanctions against Mrs Assad would prevent her entering the country remains valid.
But he refused to comment on the claims that she is seeking to leave her husband.
Turkish and Arabic media reported on Sunday that Mrs Assad, who was born to Syrian parents in London and holds dual citizenship, had filed for divorce in Russia.
The reports were denied by the Kremlin on Monday which, according to Reuters, said it was untrue that Mrs Assad was seeking to leave.
Spokesperson Dmitry Peskov also rejected reports that Assad had been confined to Moscow and had his property assets frozen.
Asked on a conference call if the reports corresponded to reality, Peskov said: “No they do not correspond to reality.”
The Assad family, including the couple’s three children, were granted asylum in Russia after the Syrian regime was overthrown by rebels.
Mrs Assad has been undergoing treatment for leukaemia, which is reportedly continuing in Russia, and the reports suggested she might want to return to London to continue care.
She was born in the UK and went to school in west London before studying at King’s College London.
Speaking in the Commons on 9 December, in the days after Assad’s regime collapse, Lammy told MPs: “I have seen it mentioned in the past few days that Asma al-Assad, as someone with UK citizenship, might attempt to come to our country.
“I confirm that she is a sanctioned individual and is not welcome here in the UK.”
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