Susan Boyle has defended her bizarre mop dance at an airport which sparked complaints from fellow fliers - insisting she has a "wacky sense of humour".

The Scottish sensation stunned travellers by dancing and singing into a mophead in a first-class lounge at London's Heathrow Airport in January, while awaiting a flight to Chicago, Illinois to film a segment on The Oprah Winfrey Show.

Airport staff asked the star to stop making noise after she began shouting obscenities and disrupting other passengers.

But the unlikely superstar insists she didn't mean to cause any offence with her behaviour - because she was only "messing about".

She tells Britain's The Sun newspaper, "(It) was just a bit of carry on (fun). I meant no harm. It was just a joke. It's my wacky sense of humour. I didn't mean any harm and if I offended anyone it was just a piece of fun. I was messing about dancing and singing."

Boyle also explains why she collapsed at the same airport just weeks later - and she is adamant there is no need for fans to fear for health.

She says, "I'm absolutely fine. I was just a wee (little) bit warm, which is why I fainted. These things get blown out of proportion."