The Liberal Democrats in the UK are calling for the British-born wife of Syrian president Bashar al-Assad to be stripped of her citizenship.

The party's foreign affairs spokesman, Tom Brake, has written to the UK Home Secretary saying Asma al-Assad should stop defending the regime's "barbaric acts".

She was educated Britain and worked as an investment banker before getting married in 2000.

She said during a 2016 interview that she refused to leave the country because she did not want people to lose confidence in her husband.

She told the Russia-24 news channel: "I never thought of being anywhere else at all...Yes, I was offered the opportunity to leave Syria, or rather to run from Syria.

"These offers included guarantees of safety and protection for my children, and even financial security.

"It doesn't take a genius to know what these people were really after. It was never about my well-being or my children - it was a deliberate attempt to shatter people's confidence in their president."

The Liberal Democrats call comes as scores of children were killed in a suicide bomb attack on bus convoy near Aleppo on Saturday.

The United Nations Emergency Relief Coordinator, Stephen O'Brien, has called on all parties to the conflict to uphold their obligations under international law and protect civilians.

"The perpetrators of such a monstrous and cowardly attack displayed a shameless disregard for human life," Mr O'Brien said.

"International humanitarian law is very clear: warring parties must protect civilians and distinguish between military and civilian targets".

Some 5,000 people were travelling from the two towns to government-controlled areas when an explosion happened near their convoy.