Green Party leader Elizabeth May is maintaining the deal struck between her and Liberal Leader Stephane Dion was not made behind closed doors.

May asserted Friday on CTV's Mike Duffy Live that Dion phoned her after she secured her position as Green Party leader and offered his help.

She and Liberal strategists have downplayed the political dealings that may have taken place in the last few days, saying the two leaders exchanged half a dozen phone calls, but there were no "backroom discussions."

"This wasn't done in the backrooms. This was done above board and in front of the cameras," maintained Liberal strategist Scott Reid while on Mike Duffy Live from Toronto.

However, political analysts and other parties maintain the deal was not out in the open.

"Did they have telephone conversations in front of the cameras?" former NDP leader ED Broadbent sarcastically asked.

Regardless, the deal between Dion and May is being touted as a historic turn in Canadian politics.

Dion announced earlier on Friday in a joint news conference with May that he won't be running a candidate against the Green Party leader in the Central Nova riding, which is currently held by Foreign Affairs Minister Peter MacKay.

Dion said he is putting partisan politics aside and throwing his weight behind May, who will fight to win her party's first seat in the next election.

"We will offer to Canadians a gesture of cooperation in order to be sure that Canada will put together all its assets as a great nation," Dion said during a press conference.

Under the terms of the non-compete agreement, May has agreed not to run a candidate against Dion and will essentially endorse him as prime minister.

"This is not a large-scale merger of parties. This is an extraordinary expression of putting principle ahead of politics as usual," May said.

During the news conference May touted Dion as the answer to Canada's climate change struggles, saying she has worked closely with him and has become convinced he is the best choice to lead Canada.

May maintained on Mike Duffy Live that she admired and trusted Stephane Dion enormously, but remained true to the Green Party and its platforms.

"I am a Green Party member and I am green to the core. That's (the Liberal Party) not my party and I will not belong to it," May said.

Criticism of the plan

Conservative cabinet ministers said the deal was a misstep by the Liberal leader.

"It's a bit surprising and I think what it amounts to is an incredible example of bad judgment on Stephane Dion's part," Environment Minister John Baird said from Washington.

He maintained that Dion's popularity, even in his own riding, is slipping.

"To have to make a deal with the leader of a fifth party to try to save his own seat and prop her up just leaves you scratching your head," Baird said.

Human Resources Minister Monte Solberg criticized Dion earlier on Friday saying the move was something his predecessors would never have done.

"I'm surprised to see ... (Dion's) first major electoral decision is to concede defeat,'' Solberg said on Friday.

"I sat in the House of Commons for a long time and battled every day with people like Jean Chretien -- someone who never backed away from a fight."

The Tory minister also said Dion needs to clarify to Canadians what aspects of the Green Party platform he is endorsing, such as the Green Party's insistence that Canada should abandon the Free Trade Agreement.

NDP Leader Jack Layton criticized the alliance at a press conference Friday calling it a backroom deal that was unfair to Canadian voters.

"I have to say it's disappointing and somewhat surprising that Ms. May, as someone who professes to be someone who stands on principal, would so quickly slip into the muck of backroom wheeling and dealing, denying people choices in an election," said Layton.

The previously unheard of level of cooperation between two supposed rivals could generate benefits and disadvantages for both parties; in particular, bolstering their environmental agenda and a possible defeat of a prominent cabinet minister.

However, many Greens are already unhappy with May for praising Dion's environmental record and saying he would make a better prime minister than Stephen Harper.

Vancouver Island environmentalist Briony Penn defected from the Greens last month and announced her decision to run for the Liberals in the coming election, saying May's praise of Dion inspired her decision.

May will need all the help she can get to beat MacKay -- a star MP hailing from a longtime Conservative stronghold.

In order to win she would have to pick up all the votes that went to the third-place Liberals in 2006 and half of the second-place NDP's votes, CP reports.

With files from The Canadian Press