LOS ANGELES (Reuters) - NBC said on Tuesday it had ordered two more seasons of its hit TV singing contest "The Voice" for the spring and fall of 2013.

"This pickup will assure the many dedicated ‘Voice' fans that this innovative show will continue to bring some of the most talented new voices to the world's attention through all of next year," NBC entertainment chairman Robert Greenblatt said in a statement.

"The Voice", which debuted as a spring show in 2011, moved to a twice a year cycle earlier this month, where it is watched by more than 12 million Americans and has drawn bigger audiences than Fox television's revamped "The X Factor."

NBC, which is majority-owned by Comcast, announced last week that singers Shakira and Usher will take the places of celebrity judges Cee Lo Green and Christina Aguilera when the show returns in the spring of 2013.

"The Voice" has proved one of the brightest lights in NBC's struggling programming schedule as the network seeks to lift itself out of its bottom place among the four leading U.S. free to air broadcasters.

As the 2012-13 TV season officially kicked off on Monday with new and returning shows on all networks, "The Voice" was the top show of the night among the 18-49 demographic most prized by advertisers, according to Nielsen data.