Madonna would rather "get run over by a train" than marry again.

The 'Celebration' singer ? whose eight-year marriage to movie director Guy Ritchie ended in December ? has dispelled rumours she is planning to wed her 22-year-old boyfriend Jesus Luz and claims marriage is the last thing on her mind.

When US talk show host David Letterman asked about possible future nuptials, she replied: "I think I'd rather get run over by a train."

However the 51-year-old star ? who has daughter Lourdes (12), son Rocco (9), and adopted children, David and Mercy, both four ? admitted there are some aspects of married life she misses.

She said: "Being a single parent means you're kind of in charge of everything. You can't say: 'Hey, can you give the kids a bath while I do something else.' There's no job sharing."

The pop star ? who was previously married to actor Sean Penn ? also revealed she looked like a "fool" when she appeared on David?s show in the 90s because she had smoked a "joint", a slang term commonly used for a cannabis-laced cigarette, before the interview.

She said: "I think I may have made a fool of myself once or twice on your show. But it wasn't that I was excited about you. I think it may have had something to do with the joint I smoked before I came on. But I didn't inhale? so it doesn't count really!"