Lib Dem MP Duncan Hames, a former Clegg aide, has asked the Home Office’s most senior civil servant to look into who made the alleged comment and whether it broke the code of conduct for special advisers.
A Tory aide is said by Mail Online to have made the remark after the deputy prime minister condemned May for “false and outrageous” accusations that the Lib Dems had put children’s lives at risk by blocking proposed surveillance legislation.
The deputy prime minister claimed it marked a low point in coalition relations but the row has now escalated.
Hames wrote to Mark Sedwill, the permanent secretary of the Home Office, saying: “You may have seen the article in the Daily Mail, entitled: Nick Clegg branded a ‘w*****’ by Theresa May aide.
“The article quotes ‘aides close to Ms May’ and ‘one source at the Home Office’ who is reported to have said: ‘Nick Clegg is a w*****’.
“Clearly the comments reported in the Mail represent an inappropriate and personal attack on the deputy prime minister.”
It is the second time a May aide appears to have got into hot water over negative briefing against a cabinet minister in recent months.
Fiona Cunningham, a media special adviser, resigned after a highly critical letter about policy on Islamic extremism from May to Michael Gove, the former education secretary, was released late at night on the Twitter feed of the Home Office.
The deputy prime minister had already written to May earlier on Thursday saying he expects an apology for her remarks about the Lib Dems blocking the communications data bill, known by critics as the snoopers’ charter.
Speaking on his Call Clegg radio show, the deputy prime minister said it was “dangerously irresponsible” of May to have blamed the Lib Dems for risking lives when she promised the Conservatives would revive plans to give the security services and police more internet snooping powers.
“To say I’ve put children at risk is a level of misinformation I’ve not witnessed in four and a half years of this government,” he said.
A Home Office spokesman said: “The permanent secretary has received Mr Hames’s letter.”
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