The same statement also recalled the Saudi's own ambassador to Canada back to Riyadh "for consultation", and halted all business and investment transactions between the two countries.
Egypt saw crucial U.S. military aid frozen past year over its own human rights record amid one of its toughest ever crackdowns on dissent, but that decision was reversed last month.
Next, came as a blow to Saudi exchange students studying in Canada on state-sponsored scholarship programmes, which have been suspended.
Since then, the Saudis have reportedly stopped accepting grain that originated in Canada and Saudi air flights have been cancelled to and from Toronto.
The issue that led to this diplomatic impasse involves Saudi police arresting human-rights activist Samar Badawi and others last week.
The Saudi foreign ministry ordered Horak to leave the country, and called the use of "immediately release" in Canada's tweet "unfortunate, reprehensible, and unacceptable in relations between states".
Airstrike on children's bus in Yemen kills at least 20
In another video, which appears to show the immediate aftermath of the strike, several children's bodies lie under a blown-up bus. Colonel Turki al-Malki, a spokesman for the Saudi-led coalition, said the missile strike was aimed at a "legitimate target".
The Saudi Ministry of Media ordered the Twitter account of the Infographic KSA, @Infographic_KSA, that posted the photo shut down, apparently unamused by its invocation of the 9/11 attack on the World Trade Center in NY. But last fall, he said, the university had 49 undergraduate and 21 graduate students registered from Saudi Arabia.
Describing both countries as "friends" and "partners" of the US, the State Department on Tuesday called on both countries to resolve the issue "diplomatically".
Amnesty International noted Ms Badawi has been repeatedly targeted and interrogated by Saudi security forces for her human rights activist. Canadian exports to Saudi Arabia totaled about $1.12 billion in 2017, or 0.2 percent of the total value of Canadian exports.
"Some of these issues we choose to discuss privately with our friends, with our partners, with our allies", Nauert said. She is a Canadian citizen whose brother, Raif Badawi, a blogger who was critical of the government, was already in jail in the Saudi kingdom.
Bahrain, UAE and the Palestinian Authority have stood by Saudi Arabia in midst of escalating pressure, according to Saudi state media Al Arabiya.
The Canadian Minister of Foreign Affairs responded by expressing concern over Saudi Arabia's actions, but resolving to stand their ground.
At the same time, it sends a strong message to European countries but also countries in the Middle East not to "mess" with Saudi Arabia, Juneau said.
The United States has asked the Saudi government for more details on the detention of activists and urged it to respect due process, a State Department official said on Monday, in the first comments by Washington since a dispute erupted.