OTTAWA - Canada's "less ambitious" climate-change plan cannot guarantee that greenhouse gas emissions will actually go down, says the head of the international body that oversees the Kyoto treaty.

The Conservative government's plan to reduce emissions is based on "intensity targets," which bases reductions on a company's industrial output rather than putting a hard ceiling on the gases as other Kyoto signatories have done.

Yvo de Boer, executive secretary of the United Nations Framework Convention on Climate Change (UNFCCC), questioned the assertion that with tough enough intensity targets an absolute reduction would occur.

"You can still see a reduction in absolute terms, but you can't guarantee how much the reduction is going to be in absolute terms," de Boer said in an interview Monday from his office in Bonn, Germany.

"If you have a very stringent relative reduction target, but your economy grows by 30 per cent, then your emissions could still end up going up."

De Boer suggested there is some confusion over how Canada intends to live up to the Kyoto Protocol, which it signed in 1997. To date, no official has said the government is withdrawing from the treaty but the Kyoto targets have been abandoned.

The Conservatives have said meeting Kyoto targets would have created an economic disaster for the Canadian economy.

"It's interesting that while it would appear that the government has set itself a new target with a new base year, which of course it's free to do, that target is less ambitious than the commitment it has under the Kyoto Protocol," de Boer said.

"The question is how this new commitment or the new policy objective relates to the international commitment or international undertaking Canada has made with the Kyoto Protocol, and also how it fits into the debate about longer term action that's currently under way."

Under the Kyoto Protocol, Canada has a number of options for meeting its targets. It can meet them by simply reducing greenhouse gas emissions; it can invest in green projects in the developing world (called Clean Development Mechanisms); it can trade carbon credits on the international market; or it can simply absorb a penalty.

Canadian officials have said the government intends to take on that penalty when the second phase of Kyoto is negotiated. De Boer said the penalty amounts to an additional one-third of whatever future reductions Canada signs on to.

De Boer noted that the measures introduced last week by the Conservative government also fall short of what other countries have proposed. The government wants to reduce greenhouse gas emissions by 20 per cent over 2006 levels by 2020 - a goal Environment Minister John Baird has said is among the "most aggressive" in the world.

According to the UNFCCC, it will be about 30 per cent over the target it had signed on to with Kyoto.

"The Europeans have put a proposal on the table to reduce their emissions by 20 to 30 per cent vis-a-vis 1990 levels, this new proposal is certainly less ambitious than that," de Boer said.

"California has made a proposal to reduce its emissions by 25 per cent from where it is at the moment. This is also less ambitious than that."

Other U.S. states, such as Maine, Vermont, Illinois, Connecticut and Washington, are also proposing steeper reductions.

De Boer confirmed that Australia, which is not a signatory to Kyoto, is on track to meet the targets it would have been assigned by the agreement.

Canada's new plan also got some advice from the British High Commissioner.

Anthony Cary spoke to a private meeting of an international think-tank a few days before Baird's release. While he acknowledged that Britain is in a different situation than Canada, having moved away from coal in the 1990s and having transferred much of its manufacturing to China, he said this is not a "get-out clause" for Canada.

"The fact is that British policy is not driven by Kyoto targets, which we have easily exceeded," Cary told the Club of Rome in remarks released Monday. "It is driven by realization, at the top levels of government, starting with the prime minister, that we have entered a new era.

"To be a successful economy in the 21st century, we need to be a low-carbon one, and there will commercial opportunities for first-movers."

Britain has already met its Kyoto targets and is proposing further reductions of between 26 and 32 per cent from 1990 levels by 2020.

The second phase of Kyoto, which is scheduled to be sealed by 2009 and to kick in after 2012, will be one of the hot topics at the next G8 meeting in Germany this June. Baird has said that Canada is committed to the next phase, and is working to bring other countries on board, particularly in the developing world.