Izzard said at a Labour Party conference he would stand for the 2020 mayoral nomination, which drew cheers from the crowd. Last year, Labour leader Ed Miliband revealed the actor was his preferred candidate.
Some question why he wouldn't run in 2016, but Izzard is currently touring his latest stand-up act, "Force Majeure," which will run through 2014.
The 2016 field is also a crowded one, with MPs Tessa Jowell, Sadiq Khan and David Lammy interested, though there is no overwhelming favorite for Labour. Jowell, who is speculated to only be standing for one term, supported Izzard's intention to enter politics.
"Eddie is a man of enormous substance, generosity and conviction. His decision to do this is a vote of confidence in Labour," Jowell said.
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