Political donations in cryptocurrency should be subject to an urgent temporary ban to stop foreign interference in British elections, the chair of the national security committee has said.

Matt Western, who leads the committee of MPs and peers, said a moratorium was needed until the risks of donations in cryptocurrency have been dealt with – including adequate checks on the source of the money.

The committee also called for a review of sentences for electoral offences, suggesting more of a deterrence was needed, with police highlighting that many covert surveillance measures can only be used for crimes that would lead to jail time of at least three years.

He wrote to Steve Reed, the cabinet minister in charge of electoral finance, asking…