Cheryl Cole `taking elocution lessons`

The singer has a strong 'Geordie' accent from North East England, and according The Mirror, bosses on the show are keen for her to ditch the twang so that she can be understood in line with American rules.

Chiefs at US channel Fox are said to have put her in touch with Hollywood voice coach Bob Corff, who worked with Sharon Osbourne, and the pair have come up with a list of words to focus on.

And a source told the newspaper, 'If audiences and contestants can't understand her it is actually a regulatory offence.'

A second source added, 'Cheryl will be told not to use the word 'babe' to describe a pretty girl. Other key words she's being taught include a 'hard I' for words such as vitamin, saying 'pants' and not 'trousers', 'butt' not 'bum' and 'cookies' not 'biscuits'.

'Another key concern is her Geordie pronunciation of the vowel 'u'. Americans pronounce it 'oo' – as in 'tooning'. They also want to clamp down on her saying 'pet' which literally means 'animal' in the States.'