Officials have approved a long-anticipated report that will say global warming is "very likely" caused by human activity, said delegates at the climate change conference in Paris, which Environment Minister John Baird is attending.

Dozens of scientists and bureaucrats are working behind closed doors to finalize the new report by the Intergovernmental Panel on Climate Change.

The IPCC will release the report, which must be unanimously approved, on Friday at a news conference in Paris.

Three participants told The Associated Press the group approved the term "very likely" in Thursday's sessions.

That term means they agree there is a 90 per cent chance that global warming is human-caused.

There had been speculation that the delegates might try to modify the wording to "virtually certain," which means a 99 per cent chance that the earth is getting warmed because of human activity.

The last report, in 2001, said global warming was "likely" caused by humans.

The report, which will serve as a summary for policymakers around the world, will also say that global warming has contributed to stronger hurricanes.

The panel approved wording saying man-made global warming can "more likely than not" be blamed for an increase in hurricane and tropical cyclone strength since 1970, delegates reported.

In 2001, the same panel had said there was not enough proof to reach such a conclusion.

The new report marks a striking contrast from a November 2006 statement by the World Meteorological Organization, which helped found the IPCC.

The meteorological said it could not link past stronger storms to global warming.

A draft of the report also reportedly predicts a rise in temperatures of between 2.5 to 10.4 degrees by 2100.

Wording requires consensus from all countries, including the United States and oil-rich countries such as Saudi Arabia.

Officials credited head of the panel session, top U.S. government climate scientist Susan Solomon, with pushing the agreement in just an hour-and-a-half.

Some delegates told AP that Chinese officials expressed opposition to strong wording on the global warming statement.

Meanwhile, Environment Minister Baird has been sent to Paris by Prime Minister Stephen Harper to be briefed by a group of scientists whose work helped initiate Kyoto, The Globe and Mail reported Thursday.

French President Jacques Chirac is also expected to ask Baird for Canada's support for a new United Nations environment organization.

Baird's spokesperson, Mike Van Soelen, would not confirm whether Canada would support the initiative.

Harper also said Thursday that he was open to participating in a summit on global warming being called for by UN Secretary-General Ban Ki-moon.

"I have not received an invitation from the United Nations Secretary-General," Harper told the Commons. "However, if we did, we would accept... we all realize this is a serious environmental problem that needs immediate action."

Meanwhile, Liberal Leader Stephane Dion has tabled an opposition motion calling on the prime minister to reaffirm Canada's commitment to the Kyoto Protocol on climate change.

Coming after a five-year-old letter surfaced in which Prime Minister Stephen Harper called the protocol a money-sucking socialist scheme, Dion's motion calls on the House of Commons to declare that there is "overwhelming scientific evidence'' that climate change is the result of human activity.

With files from The Associated Press and The Canadian Press