President Donald Trump said immunity should be offered to former national security adviser Michael Flynn in exchange for testifying to congressional inquiries into Russian interference in the US election — probes both men dismissed as a “witch hunt”.

Mr Trump on Friday backed the man he fired after only 24 days as his top national security aide with an early morning tweet: “Mike Flynn should ask for immunity in that this is a witch hunt (excuse for big election loss), by media & Dems, of historic proportion!”

Mr Flynn’s lawyer on Thursday said the former general had offered to testify in the House and Senate intelligence committees’ probes of Russian interference in American politics only if he had reasonable assurances that he would not be targeted for prosecution.