Mariah Carey has delayed a music awards ceremony by four hours.

The singer is currently promoting her 14th solo album Me. I Am Mariah... The Elusive Chanteuse. A launch party was due to take place ahead of the World Music Awards in Monaco on Tuesday evening, but when it failed to kick off on time it had a knock-on effect on the whole night.

'Mariah was meant to be at the [venue the Monte Carlo Sporting Club] at 5.30pm but her album launch was put back to 9.30pm,' a source told British newspaper The Mirror.

'The whole event has been delayed. It's not great.'

The mishap meant big name stars such as Miley Cyrus and Leona Lewis had to rearrange their schedules at short notice.

It's not known why Mariah was running late, although it was unlikely to be down to the lighting. She brought along a professional she always travels with to ensure she looks her best in photos.

'She likes to have her lighting man wherever she goes to make sure the lighting is right. That's really important to her,' an insider said.

The singer didn't seem overly concerned about the hold up and tweeted fans to let them know she was on her way.

'We don't know why Mariah is late, she's just being Mariah,' a spokesperson for the event said.

It wasn't the only issue the 22nd annual event faced. It's reported that Sharon Stone was supposed to present at the ceremony, but had to be replaced by Pamela Anderson. The former Baywatch star wore a long white gown on the white carpet and ditched the cropped locks she's been rocking lately, instead sporting a full head of extensions.

'Sharon Stone has pulled out last minute and I've just been asked to stand in, it's crazy,' she said. 'They've just asked me to read through the script right now, just as I arrived.'

Flo Rida, Kellan Lutz, Jason Derülo, Nina Dobrev, Ricky Martin and Fall Out Boy were among the stars to grace the red carpet.