Katy Perry [Photo/Agencies]

Katy Perry and John Mayer collaborate

Singer Katy Perry named UNICEF Goodwill Ambassador

The star's song 'Roar' has been shortlisted for both the Best Pop Performance and Best Pop Song prizes for the ceremony in January, and she tweeted following the announcement to share her excitement.

She wrote: "Well, that's a great way to wake up! Thank you @TheGRAMMYs for my TWO nominations!"

Many of her fellow stars also took to Twitter to share their thoughts on the nominations - which were revealed on?December 6, 2013?- including Taylor Swift.

She was named among the forerunners for Album of the Year, Best Country Song, Best Country Duo/Pop Performance and Best Country Album, and couldn't believe it.

She gushed: "I LOVE YOU GUYS WE GOT AN ALBUM OF THE YEAR NOMINATION AND I AM TOO EXCITED TO USE PUNCTUATION (sic)"

Elsewhere, Robin Thicke was pleased with getting the nod for Record of the Year, Best Pop Duo/Group Performance and Best Pop Vocal Album.

He said: "What an incredible honor, thank you to the Grammy committee for the nomination. This is the icing on the cake for this year. @TheGRAMMYs"