USHER,BEYONCE,LADY GAGA,KATY PERRY AND OTHERS SET TO PERFORM IN OBAMA S INAUGURATION FESTVAL

The larger-than-life pop star will sing at Tuesday's ball for White House staffers, a person familiar with the inauguration let slip today.

The staff ball is typically a private affair and last time around Obama's people were treated to a special performance from the President's good pal Jay-Z.

Performance: Larger-than-life popstar Lady Gaga, pictured, will sing at Tuesday's ball for White House staffers

Reprising her role: Beyonce will appear at the second inaug

COUPLES ALERT KATY PERRY AND JOHN MAYER

Sorry guys!

But your silence regarding this coupling is about as OBVIOUS as Milaand Ashton's was!

Katy Perry and John Mayer have been spotted hanging out - and swapping saliva - ALL over El Lay the past few weeks, and last night was no exception, as the pair were hounded by paparazzi as they left a house party in Los Feliz!

Just look at them (above)!

They may not have been holding hands, but we're sure they were saving THAT for the car ride!

Perhaps they were on their way to another Four Seasons sleep-over!

Oo la la!

C'mon, guys! Spill the deets!

PEREZ