Labor hopes Peter Garrett will appeal to young and green voters

He had been invited to stand as a candidate in a Sydney stronghold by Labor's new leader, Mark Latham.

Mr Latham hopes the singer, also known as an environmental activist, will appeal to young and green voters.

A general election is due this autumn, and polls suggest John Howard's ruling alliance and Labor are very close.

Correspondents say some within Labor are unhappy that an outsider has been given an almost guaranteed entry to parliament.

But Mr Latham brushed aside those concerns, saying that he thought the tall, bald rock star could have a promising political career.

"I'd be surprised that if at some time in the future Peter wasn't a frontline minister in a Labor Government," Mr Latham told a press conference in Mr Garrett's probable future constituency of Kingsford Smith.

Politics is not a perfect game... and yet it is the best game we have to making the country work better Peter Garrett

"He brings passion, conviction, energy to our cause and that's very important," Mr Latham said on Thursday.

Mr Garrett himself, the former front man of rock group Midnight Oil, was optimistic about his role.

"Politics is not a perfect game... and yet it is the best game we have to making the country work better," he said.

Mr Garrett, 51, stood for the Nuclear Disarmament Party in a federal Senate (upper house) election in the 1980s, but was narrowly defeated.

He said Labor's support of the Kyoto protocol, an international treaty designed to stem carbon emissions believed to cause global warming, was his key motivation for entering politics.

"That is one of the most compelling environmental and social and national and international issues that we face," he said.

"The Howard government is virtually silent on it, Labor is not. I feel very comfortable with that."

Prime Minister John Howard said Mr Garrett's strong environmental views were his weakness.

"You don't want extreme green attitudes because extreme green attitudes are anti-investment and anti-jobs," Mr Howard told reporters.

"It's not much good having a pristine environment in a bankrupt country."

The prime minister also attacked the rock singer's political credibility after media reports , which Mr Garrett has denied, that he did not vote in the last three elections.

The next election is expected within months, and polls suggest Mr Howard's conservative party and Labor are very close.