Australian Prime Minister Kevin Rudd on Sunday named September 7 as the election date, hoping to complete a stunning political comeback by keeping the centre-left Labor Party in power three years after it ousted him.

Kicking off an election campaign set to focus on the economy and a decision to send asylum-seekers to Papua New Guinea and Nauru, Rudd met with Governor General Quentin Bryce in Canberra to pave the way for the polls.

"It's on. A few moments ago I saw the governor-general and asked that she dissolve this parliament and call the federal election for September 7," Rudd said in an email to Labor supporters.

"Australians now face a choice. And the choice couldn't be starker. I have a positive vision about the country we can be."

Rudd became prime minister for a second time in late June when Labor members of parliament voted to remove the nation's first woman leader, Julia Gillard, for former diplomat Rudd in hopes of saving the party from catastrophic electoral defeat.

Rudd's first prime ministership, which began with his landslide victory over conservative leader John Howard in 2007 polls, ended suddenly in mid-2010 when his Labor colleagues turned on him and voted in Gillard.

He now faces a conservative opposition led by Tony Abbott, a former minister in Howard's government, in the election which had to be held before November 30.