APEC leaders have reached a consensus on climate change that involves no hard targets for reductions in greenhouse gases.

Australia's Prime Minister John Howard said Saturday that the deal was "a very important milestone in the march towards a sensible international agreement on climate change."

Howard said the agreement had the United States and China -- two nations reluctant to act on fighting climate change -- both endorsing "a long-term aspirational global emissions reduction goal."

The Sydney Statement reads: "The world needs to slow, stop and then reverse the growth of global greenhouse gas emissions."

The leaders placed no timeline on that process.

"We agree to work to achieve a common understanding on a long-term aspirational global emissions reduction goal to pave the way for an effective post-2012 international arrangement," said the statement.

Canada and Japan were singled out in the text of the document as having played a key role in achieving the agreement.

Instead of hard targets, the APEC leaders agreed to increase "energy intensity" -- the efficiency with which energy is used in production -- 25 per cent by 2030.

That translates into a 1 per cent annual reduction.

Environmentalists generally oppose intensity-based targets because if overall production rises, emissions can still increase. Climate scientists say to keep the global temperature rise to two degrees Celsius, emissions have to start declining to 50 per cent below 1990 levels by 2050.

In April, the Conservative government in Canada unveiled a plan to regulate emissions from large industrial operations that relies on intensity-based targets.

The Kyoto Accord, which became law in 2005, called for 38 developed countries to cut greenhouse gas emissions by an average of five per cent below 1990 levels by 2012.

Kyoto isn't even mentioned in the Sydney statement.

The United States and Australia both refused to ratify Kyoto, partly on the grounds that it would hurt their economies. The predecessor parties to Canada's governing Conservatives opposed Kyoto.

Sydney statement attacked

"Howard's aspirational targets are rubbish. He is trying to undermine the Kyoto protocol," said Australian Green Party Senator Kerry Nettle at a demonstration in downtown Sydney on Saturday.

In April, Alexander Downer, Howard's own foreign minister, said that an aspirational target is not a real target.

Canadian environmentalists also had little praise for the statement.

"In the face of environmental calamity, we have political cowardice," John Bennett, executive director of ClimateforChange.ca, said in a release from Ottawa.

"If the APEC statement is the platform for future action on climate change, then the world is in trouble," added Catherine Fitzpatrick, a Greenpeace energy campaigner.

Canadian officials insisted that getting large, developing nations on board and the target numbers themselves are notable.

"Both were important achievements," one official told The Canadian Press.

Canada and Japan were singled out in the text for their efforts in getting the agreement.

Sandra Buckler, Harper's director of communications, credited the prime minister personally for helping get the deal done.

"I would just say bluntly that when Canada speaks now, it speaks with credibility," she said Saturday in Sydney.

After the summit ends Sunday, Harper will travel to Australia's capital city of Canberra. He will give an address to Australia's parliament, the first Canadian prime minister to do so.

Climate change remains on the international agenda this year.

U.S. President George Bush will hold talks late this month. In December, the United Nations will hold a conference in Bali to discuss a post-Kyoto treaty.

With files from The Canadian Press