Jeremy Hunt, the foreign secretary, and Gavin Williamson, the defence secretary, may have to hand over their mobile phones

Cabinet ministers are expected to be interviewed as part of the government’s inquiry into how sensitive information about the Chinese telecoms company Huawei was leaked from a meeting of the National Security Council.

Gavin Barwell, Theresa May’s chief of staff, is understood to have warned that if the identity of the leaker is established they will be sacked even if they are a serving minister.

Yesterday ministerial aides were issued with questionnaires by Mr Barwell, who told them that anyone found to be responsible for the leak “will not be a member of the government for much longer”.

The Daily Telegraph, which published details of the initial leak, said that the questionnaires demanded to know where the advisers were after the NSC meeting on