Lady Gaga, Soundgarden and Green Day were widely tipped Tuesday (Feb. 16) as headliners for the 2010 Lollapalooza music festival on Aug. 6-8 in Chicago. Arcade Fire and the Strokes are also rumored to be topping the annual festival's lineup.

The news first surfaced on The Daily Swarm, which cites "multiple industry sources" as confirming that Gaga, Green Day and the recently reunited Soundgarden will headline the fest. It also reports that three additional headliners will be confirmed when the full Lollapalooza lineup is officially announced, which in past years has typically occurred in April.

Gaga is set to begin a run of dates in the U.K. (promoted by AEG Live) on Feb. 18 at the MEN Arena in Manchester, followed by shows in Australia, New Zealand and Japan, which are all almost sold out. It is expected that Gaga will play arenas in Europe some time this spring, then North American arenas in the summer. These will be her first full-blown arena tours in both territories, but this year will mark Gaga's second Lollapalooza appearance, having performed as a  virtual unknown on a side stage in 2007.

 Soundgarden announced that it will reunite for concerts in 2010 via a New Year's Eve Twitter message from frontman Chris Cornell which directed fans to a new Web site, Soundgardenworld.com. Sources told Billboard the group is weighing offers from several major U.S. and international festivals. The Lollapalooza appearance could possibly be the first by the Seattle rock quartet -- Cornell, guitarist Kim Thayil, bassist Ben Shepherd and drummer Matt Cameron --since splitting up in the spring of 1997. But a Soundgarden tour routing is still a work in progress, due to Cameron's prior commitments to play with Pearl Jam in the spring and summer.

The Chicago Tribune, meanwhile, reports that the the aforementioned three headliners are "nearing confirmation" along with the Arcade Fire and the Strokes, who themselves are returning from a long hiatus and recording their first album since 2006's "First Impressions of Earth."

A representative from C3, Lollapalooza's promoter, declined to comment on any of the rumored headlining acts.

Last year's Lollapalooza was the third highest grossing music festival of 2009, according to Billboard Boxscore. The festival grossed $14,082,461 and and was attended by 225,000 people over three sold-out days. -billboard.com