Canada has announced sanctions against 27 high-ranking officials in the government of Syrian President Bashar al-Assad.

Foreign Affairs Minister Chrystia Freeland says in a statement that those people are now subject to an asset freeze and dealings prohibition.

Freeland says adding their names to the sanctions list is part of the international push to put pressure on the Assad regime to end indiscriminate violence against its own people, following this month's apparent chemical weapons attack, and engage in meaningful negotiations.

On Thursday, Assad said the allegation that his government is behind a chemical attack is "100 per cent fabrication."

Earlier this week, Freeland urged Russia, a longtime a supporter of Assad, to break with the Syrian president and help broker his departure in order to establish a lasting peace in the troubled region.

Last week's chemical weapons attack in southern Idlib is a war crime and is unacceptable. - Chrystia Freeland , Canada's foreign affairs minister

Freeland says the new sanctions against key officials are part of Canada's continued efforts to pressure the Assad regime to stop the violence against innocent children, women and men.

The statement issued Friday says Canada is contributing to investigations on the use of chemical weapons and the collection of evidence to support the prosecution of war crimes and crimes against humanity in Syria.

"Last week's chemical weapons attack in southern Idlib is a war crime and is unacceptable," she said. "Canada is working with its allies to end the war in Syria and hold those responsible to account."

Canada has committed $1.6 billion to efforts in the region to provide humanitarian, security, stabilization and development assistance, in addition to having welcomed more than 40,000 Syrian refugees to Canada.