Boris Johnson rules himself out of PM race

Boris Johnson, a prominent campaigner for British withdrawal from the European Union, says he will not be a candidate for leadership of Conservative Party.

Johnson's decision means Justice Secretary Michael Gove and Home Secretary Theresa May are front-runners in the race.

They and others will compete to succeed Prime Minister David Cameron.

Johnson, announcing he will not stand as Conservative leader says: "Having consulted colleagues and in view of the circumstances of Parliament I have concluded that person cannot be me."