The career diplomat with two plum roles

SIR Mark Sedwill combines roles as both Britain’s top civil servant and Theresa May’s national security adviser.

Last October, he was appointed Cabinet Secretary by the Prime Minister after Lord Heywood retired through ill health.

In an unprecedented move, Mrs May allowed the 54-year-old to retain his existing role as national security adviser.

She cited the Government’s crisis over Brexit to justify installing her long-standing lieutenant without a formal recruitment

process. It was unclear if this was a temporary arrangement.

But in February, Sir Mark said his role had been permanently merged with his security brief to help ‘make a success of Brexit’.

Sir Mark was Mrs May’s permanent secretary at the Home Office from 2013 until she entered Downing Street in 2016. Before then his area of expertise had been in foreign policy.

He started his diplomatic career at the Foreign and Commonwealth Office in 1989 and was posted to Egypt, Cyprus and Pakistan before becoming private secretary to foreign secretary Jack Straw before the 2003 Iraq war, and ambassador to Afghanistan in 2009