Beyonce Knowles says being idolised by US President Barack Obama's daughters is terrifying.

The 'Single Ladies' singer met Malia, 10, and seven-year-old Sasha when she performed Etta James' hit 'At Last' at the Presidential inauguration in January.

A few days later, the 27-year-old singer was shocked when Barack's wife Michelle Obama phoned Beyonce to say her daughters are fans of her music.

Beyonce told America's Vogue magazine: "She told me she was very happy that her girls have someone like me to look up to. And I'm like, 'Oh, my God.'

"You have to feel fortunate to be one of the people whom parents don't mind their children looking up to. The older I get, the more I think about the amount of influence I have on these young girls, and it's scary sometimes.

"But I also understand how lucky I am to have that."

Beyonce also praised her family for helping her stay grounded and down to earth and her husband, rapper Jay-Z, for teaching her to be more discerning.

She said: "I definitely have learned to be a little more picky from Jay. Because if something makes a lot of sense to everyone else, if he doesn't feel it, he's like, 'I don't want to talk about it.' Which is great."