Saudi Arabia has suspended new trade and investment with Canada after Ottawa's foreign ministry urged the Gulf Kingdom to release detained civil rights activists, official Saudi Press Agency reported on Sunday.

Riyadh had given the Canadian ambassador 24 hours to leave the country and recalled its own ambassador to Canada, a statement by the Saudi foreign ministry said.

The decision, carried on the official Saudi Press Agency, caught diplomats in Riyadh off guard. Both the Saudi and Canadian ambassadors were away on leave at the time.

The kingdom will suspend educational exchange programmes with Canada and move Saudi scholarship recipients to other countries, Saudi-owned Al Arabiya reported on Monday.

"It would be a shame for those students if they are deprived of the opportunity to study here," Canada's Foreign Minister Chrystia Freeland told reporters.

But she said that Canadian policies towards human rights will not change.

"Canada will always stand up for human rights in Canada and around the world, and women's rights are human rights," Freeland said.

Neighbours and allies Bahrain and the United Arab Emirates said they stood with Riyadh, although they did not announce similar measures.

Saudi state airline Saudia said it was suspending flights to and from Toronto, Canada's largest city.

It remains unclear if the new trade freeze will affect existing annual Saudi-Canadian trade of nearly $4 billion and a $13 billion defence contract.

The moves followed vigorous calls by Canada for the immediate release of human rights activists swept up in a new wave of detentions, AFP said.

The Canadian embassy in Riyadh had said it was "gravely concerned" over the wave of arrests of rights campaigners in the kingdom, including award-winning women's rights activist Samar Badawi, the sister of jailed dissident blogger Raif Badawi.

Raif Badawi's wife Ensaf Haidar lives in Canada and recently became a Canadian citizen.

This was the Statement from Canada issued on Friday. Saudi said it’s interference in internal affairs pic.twitter.com/4ZJqDKpHnp — Joyce Karam (@Joyce_Karam) August 5, 2018

"We urge the Saudi authorities to immediately release them and all other peaceful #humanrights activists," the Canadian embassy tweeted on Friday.

The Saudi foreign ministry later tweeted: "The kingdom of Saudi Arabia... will not accept interference in its internal affairs or imposed diktats from any country."

It added that "the kingdom views the Canadian position as an affront to the kingdom's laws and judicial process, as well as a violation of the Kingdom's sovereignty."

The Gulf Kingdom also reportedly withdrew from several educational partnerships with Canadian universities. State media outlets said that Riyadh planned to transfer 12,000 Saudi students studying at Canadian institutions to universities in the US, UK, Australia, New Zealand and Singapore.

Saudi authorities last week arrested two prominent women rights activists, Samar Badawi and Nassima al-Saadah, and held them incommunicado, Saudi human rights groups said.

The arrests followed a spate of detentions of women's rights activists in the run-up to the end of the ban on women driving in the kingdom in late June.

Saudi crackdown: Two high-profile women activists detained Read More »

Badawi is a recipient of the 2012 International Women of Courage Award by the US State Department, in recognition of her campaigning for women suffrage and her challenging of the male guardianship system in the Gulf kingdom.

Al-Saadah was among the first women to run for office in Saudi Arabia in 2015 as part of a campaign for women’s political rights. She was, however, disqualified and barred from running.

The Saudi foreign ministry voiced anger over the Canadian statement.

"It is very unfortunate that the words 'immediate release' appeared in the Canadian statement... it is unacceptable in relations between countries," the ministry said.

"Canada and all other nations need to know they can't claim to be more concerned than the Kingdom over its own citizens."

An official Saudi government Twitter account shared - then promptly deleted - a graphic denouncing the Canadian statement showing a plane flying towards the CN tower in Toronto. The image was interpreted by social media users as a tasteless allusion to the 9/11 World Trade Center attacks.

In 2014, the Canadian unit of US weapons maker General Dynamics won a contract worth as much as $13bn to build light-armoured vehicles for Saudi Arabia, in what Ottawa said at the time was the largest advanced manufacturing export win in Canadian history.

Meanwhile, the United States said on Monday that it has asked the Saudi government for more details on the detention of activists.

"We have asked the Government of Saudi Arabia for additional information on the detention of several activists," a State Department official said in a statement, calling both Saudi Arabia and Canada "close allies."

"We continue to encourage the Government of Saudi Arabia to respect due process and to publicise information on the status of legal cases," the official added.