A final international agreement setting new targets to slash greenhouse gas emissions would be "too ambitious" to solidify in this week's round of climate talks in Bali, the UN chief said Wednesday.

A delegate to the U.N. climate conference in Bali, Indonesia, walks past a sign put up by an environmental group on Wednesday.
(Binsar Bakkara/Associated Press)

"Practically speaking, this will have to be negotiated down the road," UN Secretary General Ban Ki-moon told reporters, when asked whether delegates could agree to including greenhouse gas emissions targets in a new climate accord.

While the European Union and developing countries favour reductions targets for greenhouse gases, the U.S. opposes setting specific limits.

Wednesday's talks in Bali brought together ministers from more than 130 nations for a high-level segment of a two-week summit, which ends Friday. Delegates are working to set an agenda for talks on a new climate pact to replace the Kyoto Protocol.

An early draft statement for the conference, which the Associated Press obtained this week, asks that rich countries consider cutting emissions blamed for global warming by between 25 per cent and 40 per cent below 1990 levels by the year 2020.

Achieving that goal will be a challenge, Ban said.

"Realistically, it may be too ambitious" for this week's summit in the Indonesian resort island, he said, downplaying expectations for strong commitments in the final document.

"I urged the U.S. government to exercise flexibility, as the largest economic power of the world," Ban added.

U.S., Canada take similar stance

Meanwhile on Wednesday, Canadian Environment Minister John Baird said from Bali that Canada's 700 biggest polluters will have six months to report on their greenhouse gas emissions. He said the data collected will be used to impose binding reduction targets sometime next year.

The targets are a key part of the Conservative government's plan to reduce greenhouse-gas emissions by 20 per cent by 2020 — a figure that falls short of the Kyoto Protocol's requirements.

A number of environmental groups have been critical of Canada, which has adopted a similar bottom line as the U.S. in Bali.

The U.S. has argued that economic powerhouses such as China and India, which were not subject to the mandatory reductions under the Kyoto Protocol, must also commit to limits if there is to be any progress in curbing climate change.

Harlan Watson, a lead U.S. negotiator at the Indonesia talks, suggested that including specific emissions reduction targets in the final document would prejudice negotiations over the next two years aimed at crafting a new global warming pact to take effect after Kyoto expires in 2012.

"The reality in this business is that once numbers appear in the text, it prejudges the outcome and will tend to drive the negotiations in one direction," Watson said.

With files from the Associated Press