Boris Johnson poses for resignation photo

By AAP Newswire

Amid one of the deepest crises of Prime Minister Theresa May's premiership, Boris Johnson has posed for a photograph of himself, pen poised, ready to resign as foreign minister over Brexit.

Johnson, frowning slightly and staring directly at the camera, sits behind a desk in a panelled room at his official London residence with his resignation letter - which bemoaned the death of the "Brexit dream" - at the ready.

It is highly unusual for senior British ministers to be photographed with their resignation letters and the picture provoked criticism from some opponents of Brexit.

"The fact that @BorisJohnson arranged for a photoshoot of himself signing his resignation letter for the front pages tells us everything we need to know about him," opposition Labour lawmaker David Lammy said on Twitter.

"Self-obsessed, vain egomaniac devoid of substance caring only about himself and advancing his career. Good riddance," Lammy said.

The picture was published on the front page of The Daily Telegraph on Tuesday.