The letter said Sudan should not be held responsible for the actions of the regime of ex-President Omar al-Bashir, who was forced out of power earlier this year following a popular uprising.

The letter was signed by politicians, academics, activists, and professionals in the diaspora.

Sudan was added to the US list of state sponsors of terrorism in 1993 after it was accused of harbouring Islamist militants. At the time, Osama Bin Laden and his al-Qaeda network were among those based there.

One of the 79 signatories of the letter, Sara Abdigalil, the president of the Sudan Doctors Union in the UK, told BBC Newsday that the sanctions have limited investment options in Sudan.

"Things have changed," she said.

"Lifting the sanctions has got benefits not only for the people of Sudan but globally. If you talk about terrorism without having [a] sort of economic stability it will be difficult to fight terrorism," she added.