Pop diva Beyonce will sing the national anthem before hundreds of thousands of onlookers at US President Barack Obama's inauguration ceremony on January 21, organizers said Wednesday.

On a stage specially constructed for the event at the foot of the Capitol, the singer -- a long-time supporter of Obama -- will belt out "The Star-Spangled Banner" before Obama's cabinet, lawmakers and the public.

Chart-topping pop singer Kelly Clarkson, the first winner of "American Idol," and veteran singer-songwriter James Taylor will also perform at the ceremony to mark the start of Obama's second term.

At Obama's first inauguration in 2009, soul legend Aretha Franklin gave a stirring rendition of another US patriotic song, "My Country Tis of Thee". This time around, Clarkson will perform it.

Beyonce and her rap star husband Jay-Z were key backers of Obama's 2012 re-election campaign, hosting a fundraising event in New York for the Democratic incumbent.

Beyonce, who sang at one of the inaugural balls in 2009, is starting the year strong -- she will also perform the much-watched halftime show at the Super Bowl on February 3.

Richard Blanco, who was born in Spain to Cuban exiles, will serve as the inaugural poet, the first Latino and first openly gay poet to have the honor of reading his work at an inauguration ceremony, organizers said.

"Richard's writing will be wonderfully fitting for an Inaugural that will celebrate the strength of the American people and our nation's great diversity," Obama said in a statement.

Blanco follows in the footsteps of Maya Angelou, who read "On the Pulse of Morning" at Bill Clinton's first inauguration in 1993.

Obama will take the oath of office in a private ceremony on January 20, a date stipulated by the US constitution. The public inauguration ceremony will take place on January 21.