Saudi Arabia has withdrawn its ambassador to Canada, demanded his counterpart, Ambassador Dennis Horak, leave the kingdom within 24 hours and threatened a trade halt after Canada criticised its arrest of two women’s rights activists.

On Monday, Saudi Arabia’s foreign ministry accused Canada of “overt and blatant interference” and “a grave and unacceptable violation”.

The dispute appears centred around a tweet by Global Affairs Canada, managed by the foreign ministry, calling on the kingdom to “immediately release” women’s rights activists recently detained by the kingdom.

Canada is gravely concerned about additional arrests of civil society and women’s rights activists in #SaudiArabia, including Samar Badawi. We urge the Saudi authorities to immediately release them and all other peaceful #humanrights activists.

— Foreign Policy CAN (@CanadaFP) August 3, 2018

Just two words in Canada’s statement appeared to have especially infuriated the Saudis.

“Using the phrase ‘immediately release’ in the Canadian statement is very unfortunate, reprehensible, and unacceptable in relations between states,” the Saudi foreign ministry said.

Among those recently arrested was Samar Badawi, whose brother Raif Badawi was arrested in Saudi Arabia in 2012 and later sentenced to 1000 lashes and 10 years in jail for criticising clerics. His wife, Ensaf Haidar, is now living in Canada.

Canadian Foreign Minister Chrystia Freeland similarly denounced the arrests on Thursday.

“Very alarmed to learn that Samar Badawi, Raif Badawi’s sister, has been imprisoned in Saudi Arabia,” she wrote on Twitter.

“Canada stands together with the Badawi family in this difficult time, and we continue to strongly call for the release of both Raif and Samar Badawi.”

Very alarmed to learn that Samar Badawi, Raif Badawi’s sister, has been imprisoned in Saudi Arabia. Canada stands together with the Badawi family in this difficult time, and we continue to strongly call for the release of both Raif and Samar Badawi.

— Chrystia Freeland (@cafreeland) August 2, 2018

Among Saudi Arabia’s threatened recriminations was a freeze on all new business between the kingdom and Canada. This might prove a threat with real consequences, as Canada imports about 10 per cent of its crude oil from the Saudis.