Vogue deputy editor and David Cameron's sister-in-law issues stark warning for Theresa May

'They will come for you, I am afraid one day, Prime Minister'

Theresa May (EPA)

The deputy editor of British Vogue has issued an ominous warning to Theresa May of what lies ahead for her as the incumbent Prime Minister.

Emily Sheffield, David Cameron’s sister-in-law, urged Ms May to champion the achievements of her predecessor instead of their differences and prepare for stormy waters ahead.

“They will come for you, I am afraid one day, Prime Minister, like they did for Thatcher, Blair and Brown," writes Ms Sheffield in a piece for The Spectator.

“You need to be emblematic of so much more than just a strong leader. So as you set out your stall for the future, in these troubled times, please loudly champion the past, set your valuation high for all — especially Westminster, as your predecessor did at his last PMQs, because that’s better for our future. That’s a Britain I will vote for with or without the EU.”

In a staunch defence of Mr Cameron’s premiership, Ms Sheffield praised her brother-in-law as a decent leader and a kind, forgiving friend with a sense of humour.

She also addressed the Instagram picture quickly deleted from her account of the Prime Minister having a nap next to his ministerial red box.

“In my opinion, you brought down a good man," Ms Sheffield continues.

“To the media and the electorate he was the Prime Minister. To me, he was also my sister’s husband, who loved and protected her through truly terrible times.

“A brother-in-law who didn’t send me remonstrations the day my Instagram of his bare feet made national news, but instead a very funny text.”