Former UK Foreign Secretary Boris Johnson has reportedly split with his wife Marina Wheeler QC, after longstanding rumors of infidelity.

Wheeler, a barrister and divorce specialist, and Johnson, both 54, are living separately after 25 years of marriage, the Sun reported Thursday.

Sources told The Sun that Wheeler kicked Johnson out over fresh allegations that he had been seeing another woman.

Conservative Party sources have said Johnson may be preparing for a leadership bid following his resignation as Foreign Secretary in July.

Johnson has been accused of affairs previously, most notably with British journalist Petronella Wyatt, who claimed she aborted their unborn child.

Johnson denied those allegations, which he called an “inverted pyramid of piffle”, but he was ultimately sacked as shadow arts minister and Tory Party vice chairman in 2004 for publicly lying about the affair.

He also reportedly had an affair with journalist Anna Fazackerley and another with art consultant Helen Macintyre, with whom he fathered a child.

The existence of his illegitimate daughter became a major court case, with three appeal court judges ruling in 2013, when Johnson was Mayor of London, that the public had a right to know.

Their judgment said in part that “it is fanciful to expect the public to forget the fact that the man who is said to be the claimant’s father, and who is a major public figure, has fathered a child after a brief adulterous affair (not for the first time)”.

Wheeler, Johnson’s second marriage, had thrown her husband out of the family home twice, but the two later patched up their relationship.

The couple have four children together, and Wheeler has been credited as a key influence in his decision to back Brexit in 2016 referendum.

Recent polls put Johnson in the lead for taking over as head of the Conservative Party after Theresa May.

Follow Business Insider Australia on Facebook, Twitter, LinkedIn, and Instagram.