Foreign Affairs Minister Peter MacKay has wrapped up a meeting with his U.S. and Mexican counterparts, as part of the Security and Prosperity Partnership.

The partnership aims to harmonize regulations and standards between the three countries, and boost border security.

But one security issue that continues to divide Canada and the U.S. is Maher Arar.

In 2002, U.S. officials deported the Ottawa-based engineer to Syria, where he was tortured into making false confessions that he was involved with al Qaeda.

During a joint press conference with MacKay, U.S. Secretary of State Condoleeza Rice and Mexican Foreign Secretary Patricia Espinosa, Rice said Arar would remain on her country's security watch list.

"We respect the Canadian government concerning Mr. Arar. The United States, of course, makes decisions based on information that we have and based on our own assessment of the situation," said Rice.

MacKay responded by saying the Canadian government respects the right of the U.S. to make its own decision, but noted that Ottawa has completely exonerated Arar.

"What we have done is obviously to compensate Mr. Arar and act on the recommendations of a very public inquiry, and we have accepted and acted on all of them," said MacKay.

"The United States of America takes a very different view. On many issues, we respect the sovereignty of the United States, just as they clearly respect ours."

The officials gave little details of what was discussed during Friday's talks, which critics decried as being too secretive and possibly harmful to Canada's sovereignty.

Ottawa had earlier issued a press release saying the discussion would not move Canada closer to becoming another U.S. state.

The release offered assurances that ministers are not making secretive backroom agreements with U.S. and Mexican ministers that would undermine Canada's independence.

New Democrat MP Peter Julian said Thursday that that the group's inner workings are murky and the public needs to have a greater say on what takes place.

"We're looking at potentially 300 different areas where Canada is accepting lower American standards," he said.

"If we're talking about fundamental changes to the various policies we've adopted as a country, then the public absolutely has to have that debate.''

Ottawa responded that "the SPP outlines an agenda for co-operation among the three countries, while respecting each country's sovereignty, culture and laws."

Minister of Public Safety Stockwell Day and U.S. Secretary of Homeland Security Michael Chertoff spoke to reporters immediately after the foreign ministers.

But in an odd twist, North America's top security officials were interrupted by a brief security breach, when two protesters managed to storm the stage.

Since the SPP was formed, the leaders of the three nations have met twice. First in 2005 in Texas, then in Mexico in 2006, and they will meet again sometime later this year.

The SPP was formed in 2005 to boost trade and security in all three nations.

With files from The Canadian Press