Foreign Affairs Minister John Baird and other western leaders applied more pressure on Syria on Sunday, with a call for Syrian authorities to allow the United Nations immediate and unfettered access to the site of last week's alleged chemical attack.

Officials in Baird's office said he had separate phone conversations on Sunday with US Secretary of State John Kerry and the Foreign Minister of the French Republic, Laurent Fabius. He spoke with British Foreign Secretary William Hague on Friday.

The ministers "shared their outrage" about recent events in Syria, especially the purported use of chemical weapons, said an foreign affairs official in an email.

Prime Minister Stephen Harper also was pulling the diplomatic levers over the weekend, discussing the situation in Syria by phone on Saturday in separate conversations with British Prime Minister David Cameron and French President Francois Hollande.

Baird's office said there was agreement in the discussions the minister had that the delay in allowing inspectors, along with the bombardment of the affected areas, has likely already impaired the UN's ability to assign responsibility in the attacks.

"The regime's actions on this issue in the coming hours and days will speak louder than its words," said a statement from Baird's office released Sunday.

A visit to the site of the alleged chemical attack could come as early as Monday.

A statement on Syrian state television said Foreign Minister Walid al-Moallem and UN disarmament chief Angela Kane struck a deal and that the two sides were working to finalize the date and time of the visit.

The UN said a team of international experts is preparing to go as early as Monday to the suburb of Damascus where the purported attack took place.

Anti-government activists and Doctors Without Borders say that more than 300 people were killed in the alleged toxic gas attack. The Assad regime has denied using chemical weapons on civilians, instead pointing a finger at rebel forces.

Confirming whether chemical weapons were used carries enormous stakes, and could play a large role in determining the future course of Syria's civil war. It has reinvigorated debate about the possible use of foreign military action in the conflict.

Baird, meanwhile, is under pressure from the head of Syria's main opposition group who is visiting Canada.

George Sabra, president of the Western-backed Syrian National Council, said he wants Canada to do more to help put an end to the conflict.

"We need to see real movement now to protect Syrian people --not only statements, we need action," Sabra said Saturday, prior to a town-hall style meeting in Montreal.

Sabra, whose coalition is based in Istanbul, Turkey, is scheduled to meet Baird on Wednesday in Montreal. He is visiting Ottawa and Toronto in the meantime.

Sabra and Baird, however, don't appear to agree on how to end the bloodshed in the war-torn country.

In contrast to Baird, Sabra said he no longer believes a political solution is possible, when so many Syrians have been killed or forced from their homes.

"We have one-million children living in refugee camps," Sabra said.

"In this environment, who can talk about a political solution?"

Baird has maintained political pressure remains the best way to end the civil war.

Sabra said he wants to see action from U.S. President Barrack Obama, who has said he considers chemical weapons a "red line" in the conflict. But he said Canada should also play a larger role.

"When we think about Canada, we think about human rights. We expect a special role from Canada in this field," he said.

That message was echoed by many Syrian-Canadians who turned out to hear Sabra speak at a Montreal college.

Maher Sawaf, a 58-year-old Montrealer originally from Damascus, said he's concerned about family, friends and the country as a whole. He brought posters to the meeting that denounced the "chemical massacre" in Syria.

"We're hoping that this time, after the massacre, that a Western coalition will take action against the Syrian regime," Sawaf said.

Sabra's group has faced criticism of its own regarding treatment of women and religious minorities.

He rejected both charges on Saturday.

"We have documents that indicate word by word we will guarantee to improve the situation of women, and (we see) no difference from Muslims to Christians to Jews," he said.