Saudi Arabia said Monday it was expelling the Canadian ambassador and recalling its envoy while freezing all new trade, in retaliation for Ottawa's vigorous calls for the release of jailed activists.
The kingdom gave the envoy Dennis Horak 24 hours to leave the country, in an abrupt rupture of relations over what it slammed as "interference" in its internal affairs.
Ottawa said it was "seriously concerned" and was seeking "greater clarity" on the shock move, which was announced on Twitter by the Saudi foreign ministry.
"Canada will always stand up for the protection of human rights, very much including women's rights, and freedom of expression around the world," said foreign ministry spokeswoman Marie-Pier Baril.
"Our government will never hesitate to promote these values and believes that this dialogue is critical to international diplomacy."
The rupture, which underscores a newly aggressive foreign policy led by Crown Prince Mohammed bin Salman, comes after Canada denounced a new crackdown on human rights activists including the sister of a jailed blogger.
"The Canadian position is an overt and blatant interference in the internal affairs of the kingdom of Saudi Arabia," the Saudi foreign ministry tweeted.
"The kingdom announces that it is recalling its ambassador to Canada for consultation. We consider the Canadian ambassador to the kingdom persona non grata and order him to leave within the next 24 hours."
The ministry also announced "the freezing of all new trade and investment transactions with Canada while retaining its right to take further action".
Canada last week said it was "gravely concerned" over a new wave of arrests of women and human rights campaigners in the kingdom, including award-winning gender rights activist Samar Badawi.
"We urge the Saudi authorities to immediately release them and all other peaceful #humanrights activists," its foreign ministry tweeted on Friday.
- 'Unprecedented crackdown' -
Samar was arrested along with fellow campaigner Nassima al-Sadah last week, the latest victims of what Human Rights Watch called an "unprecedented government crackdown on the women's rights movement".
Samar's brother, blogger Raif Badawi, was arrested in 2012 and sentenced to 1,000 lashes and 10 years in jail for "insulting Islam" in a case that sparked an international outcry.
The latest arrests come weeks after more than a dozen women's right campaigners were detained and accused of undermining national security and collaborating with enemies of the state. Some have since been released.
The Saudi foreign ministry slammed the Canadian statement, signalling its growing annoyance over Western criticism of its human rights record.
"Using the phrase 'immediately release' in the Canadian statement is very unfortunate, reprehensible, and unacceptable in relations between states," the ministry tweeted.
Prince Mohammed, heir to the region's most powerful throne, has introduced a string of reforms such as lifting a decades-long ban on women drivers in a bid to overhaul the kingdom's austere image as it prepares for a post-oil era.
But the 32-year-old has simultaneously pursued a hawkish foreign policy -- including leading a blockade of neighbouring Qatar and a bombing campaign against Iran-backed Huthi rebels in Yemen -- while cracking down on dissent at home.
"The rupture in Saudi diplomatic relations with Canada reinforces how the 'new' Saudi Arabia that Mohammed bin Salman is putting together is in no mood to tolerate any form of criticism," said Kristian Ulrichsen, a fellow at Rice University's Baker Institute in the United States.
- Activists jailings -
In April, Canadian Prime Minister Justin Trudeau expressed his "serious concern" over the continued jailing of Raif Badawi to Saudi King Salman.
Badawi's wife Ensaf Haidar has been granted asylum by Canada, where she is raising their three children now aged 14, 13 and 10 as a single mother.
"The world cannot continue to look the other way as this relentless persecution of human rights defenders in Saudi Arabia continues," said Samah Hadid, Amnesty International's Middle East director of campaigns.
"It is now time for other governments to join Canada in increasing the pressure on Saudi Arabia to release all prisoners of conscience immediately and unconditionally."
But Riyadh's singling out of Canada is aimed at strongly discouraging other critical Western governments from speaking out, observers say.
"Canada is easier to cut ties with than the rest," Bessma Momani, a professor at Canada's University of Waterloo, told AFP.
"There isn't a strong bilateral trade relationship and poking the Trudeau government likely resonates with Saudi's hawkish regional allies. At jeopardy are the tens of thousands of Saudi students in Canada."
Saudi Arabia says it is expelling Canada's ambassador and recalling its own envoy to Ottawa, underscoring a newly aggressive foreign policy led by Saudi Crown Prince Prince Mohammed bin Salman
Political activist Samar Badawi of Saudi Arabia, seen here in a March 8, 2012 filer, was swept up in a Saudi crackdown on human rights campaigners
Canadian Prime Minister Justin Trudeau raised concerns in April about Badawi's jailing