Lord Browne, one of the foremost businessmen in the UK, has resigned after it was revealed he lied to the High Court.
He was chief executive of BP.
In a statement to the court earlier this year the peer said he met Canadian Jeff Chevalier while exercising in Battersea Park.
He later admitted this was untrue and apologised.
Lord Browne took his fight as far as the House of Lords in an attempt to stop Associated Newspapers, owners of the Daily Mail and the Evening Standard, publishing details of his relationship with Mr Chevalier.
In a statement Lord Browne said:
“In my 41 years with BP I have kept my private life separate from my business life.
“I have always regarded my sexuality as a personal matter, to be kept private.”
The Daily Telegraph reports Mr Justice Eady as saying that Lord Browne’s, “willingness to tell a deliberate lie to the court, persisted in for about two weeks, is relevant in assessing his own credibility.
“So too is his willingness casually to ‘trash’ the reputation of Mr Chevalier and to discredit him in the eyes of the court.”
The Daily Mail reports that Mr Chevalier alleges that Lord Browne diverted BP resources for his use and discussed company secrets with him.
He also alleges Lord Browne divulged details of discussions with the Prime Minister and the Chancellor of the Exchequer.
In his statement Lord Browne said:
“It is a matter of personal disappointment that a newspaper group has now decided that allegations about my personal life should be made public.
“Legal documents have been disclosed today containing allegations about me and my personal life.
“I wish to acknowledge that I did formerly have a four-year relationship with Jeff Chevalier.
“He has made these allegations about me and our relationship to Associated Newspapers.
“The allegations are full of misleading and erroneous claims.
“I deny categorically any allegations of improper conduct relating to BP.
“The company has confirmed today that it has found no such wrongdoing.
“My initial witness statements, however, contained an untruthful account about how I first met Jeff.
“This account, prompted by my embarrassment and shock at the revelations, is a matter of deep regret. It was retracted and corrected.
“I have apologised unreservedly, and do so again today.”
Mr Chevalier, a Canadian citizen, went to the press after Lord Browne ended their relationship last year.
He revealed that the peer, who was to step down from his job in July, effectively “kept” him.
Lord Browne, 59, met Mr Chevalier in 2002, and over the next four years provided him with a life of luxury, including paying for his accommodation, clothing and extensive international travel.
The peer also paid substantial sums of money to Mr Chevalier, and paid for a university course so that he could stay in the UK.
The High Court had previously ruled in a private sitting that as Lord Browne had taken his partner to various social events, including those connected with his duties at BP, the relationship was widely known about.
Lord Browne was one of the highest paid executives in the UK.
In 2004 he earned over £5m. He joined BP as an apprentice in 1966.
He was knighted in 1998 and created Baron Browne of Madingley in 2001.