Chris Martin has joked that his eight-year marriage to Gwyneth Paltrow is a fix-up, in an interview on US TV.

Appearing on The Ellen DeGeneres Show, the Coldplay frontman quipped that he was secretly gay and that Paltrow had been his "beard," a term used where a woman pretends to be married to a man because he is hiding his sexuality.

Leading into the conversation, DeGeneres said: "You have had a great relationship and two precious kids. And we love Gwyneth. She’s been here many times."

Martin replied, "She’s been a great beard for me now, for 10 years." DeGeneres added, "Is that right? It’s not really a real relationship?" and Martin responded, "Yes, it’s hard to believe."

The singer admitted he did not like to discuss his wife - but this is his second public reference to her within a week, despite being notoriously private about their relationship.

Last week, he told CBS Sunday Morning that marrying Paltrow was like "winning the lottery" and that he could not believe his luck.

The couple have two children together - Apple, seven, and Moses, five.

They met at a Coldplay gig in 2002 and married one year later.

My marriage is a sham, jokes Chris Martin