Nicki Minaj and Keith Urban have officially joined the American Idol judging panel.

Mariah Carey was confirmed as one of the show's new judges earlier this year, while many other names have been linked to the panel, with Nicki and Keith named as frontrunners.

Fox have now confirmed that the two stars will join Mariah along with returning judge Randy Jackson.

"Nicki's an unbelievably captivating international phenomenon who has made an indelible mark on rap and pop," Fox's Mike Darnell explained in a statement. "And Keith is another great addition to Idol he's one of the biggest stars in country music and I know that our fans and contestants will fall in love with him.

"With an unparalleled star like Mariah, fan-favourite Randy, chart-toppers like Nicki and Keith and our incomparable host Ryan [Seacrest], we've put together one of the most exciting judging panels around."

The confirmation settles months of speculation about the show's panel that saw stars including Nick Jonas, Kanye West and Pharrell Williams named as possible judges.

Jennifer Lopez and Steven Tyler announced their departure from the hit TV talent show in July.

Season 12 of American Idol starts in January.