OTTAWA - Green party Leader Elizabeth May says since her own government doesn't want her contribution at an international conference on climate change, she's offered it to the South Pacific nation of Tuvalu.

May calls it a "gross insult" the federal government has excluded her and other opposition MPs from the Canadian delegation heading to a key climate conference in South Africa.

She says she and opposition environment critics sent the Prime Minister's Office a letter offering to pay their own way to the conference in Durban and they haven't received so much as a reply.

May even tried to join the Tuvalu delegation but missed the deadline.

Rising sea levels due to global warming threaten to submerge the tiny island chain, population 10,500. The cabinet from the Maldives in the Indian Ocean has even met underwater to publicize their mutual plight.

"If my government, the Government of Canada, does not need my help, I offer it to another government, one that works for my children because the Government of Canada does not work for my children, my grandchildren," May said in French.

"Only the Tuvalu government does. I trust their delegation a lot and do not trust at all the Government of Canada and its delegation."

May says excluding her -- the lone Green party MP in the House of Commons -- is one thing. Excluding the environment critics from the official Opposition NDP and Liberals is unprecedented.

"It's really insulting and offensive to Canadian democratic principles that this government acts as if it is Parliament," she said.

"When Canada goes to an international negotiation, it doesn't go as the Harper government; it goes as Canada."

May will attend the conference as an observer but, lacking the credentials given members of official delegations, she will not be allowed to attend some of its key discussions.

"I never regarded the participation of the official Opposition on the delegation as a question mark," she said, acknowledging that with only one seat her Greens lack official party status.

"I never thought for a minute they would exclude the Liberals and the NDP."

The Conservatives appear to be as committed to killing the Kyoto protocol on greenhouse-gas emissions as they were to killing the Canadian Wheat Board and the long-gun registry, said May.

Environment Minister Peter Kent says Canada won't make a second commitment to Kyoto because the accord doesn't include some of the world's biggest emitters, such as the United States, India and China.

That, said May, is "a big fat lie."

"China, India and Brazil are all countries that ratified the Kyoto protocol."

South Africa's high commissioner to Canada, Mohau Pheko, has said some countries -- strongly hinting Canada is among them -- have been arm-twisting ahead of the Durban conference, even threatening to withdraw aid money if some delegations don't adopt their position.

"What I can say, not only of Canada but of other major partners, is threats and arm-twisting by saying that 'if you do not support our position, we will withdraw our aid packages or we will withdraw monies that we have committed on various projects in your country' -- for many countries that are vulnerable, this is really tantamount to bullying," Pheko told CBC Radio's "As It Happens."

Pheko said Canada does not want to be seen as the one to break up the talks on its own.

"So they have been actively talking to other countries to do the same. It is quite an obstructive role to, in fact, come to the talks when in essence your intention is not to be part of the Kyoto protocol.

"I think the key question then becomes: why come to the talks at all? The only other thing that we can say -- and have reports of -- is to pull other countries to their position."

In a full-page ad in the Globe and Mail newspaper this week, Nobel Peace laureate Desmond Tutu and more than a dozen other African notables called on Canada to "change course."

"Be a leader in clean energy and ... support international action to reduce global warming pollution," it said.

The ad compared Canada's strong stand against apartheid in the 1980s with its support of "multinational oil companies" today and the potential impact global warming will have on African drought and famine.

"Canada, you were once considered a leader on global issues like human rights and environmental protection," it said.

May said it's critical Canada "come back into the fold of countries prepared to be responsible citizens globally."

"This is a time for people of conscience to speak up," she said. "We are not in a position to negotiate with the atmosphere.

"We are unleashing a potential cataclysmic ... degree of climatic shifts that could wipe out human civilization."