Spy master Le Carre slams 'pig-ignorant' Johnson in 25th novel

British master spy novelist John le Carre's 25th book condemns "pig-ignorant" Boris Johnson and the "lunacy" of Brexit, according to an excerpt published in Saturday's Guardian newspaper.

Set in 2018, "Agent Running in the Field" tells the tale of Nat, a 47-year-old MI5 foreign intelligence service member with doubts about Britain's fate.

Extracts of the 87-year-old writer's book, to be released on October 17, show Nat revealing his career choice to his daughter Steff.

Johnson is still foreign secretary in the book, a position he gave up in July 2018 in protest at former prime minister Theresa May's Brexit strategy.

Describing a Britain in "free fall", Nat lists the reasons why he doubts why his country was still a democracy that worked for its people.

"A minority Tory cabinet of tenth-raters. A pig-ignorant foreign secretary who I'm supposed to be serving. Labour no better. The sheer bloody lunacy of Brexit," Nat tells his daughter.

Le Carre is a renowned europhile who joined dozens of other novelists in urging voters to support the EU in May's European parliament elections.

The poll was won in Britain by the Brexit Party of anti-EU populist Nigel Farage.

"The thing about Le Carre is that he's always been as much at home in Europe as Britain," his editor, Mary Mount, told The Guardian.

"After the (2016 Brexit) referendum, there was no choice for him except to look at where we are now."