Amnesty International says New Zealand needs to speak up for its ally Canada as it faces a diplomatic backlash for speaking out against Saudi Arabia's imprisonment of human rights activists.

"Our national identity is based on fearlessly standing up for values like equality. This is a pivotal moment for New Zealand diplomacy," said executive director of Amnesty International New Zealand, Tony Blackett.

"Either we defend our values, or we quietly endorse blatant human rights violations."

When Canada spoke out last week against Saudi Arabia, it was met with a heavy-handed response from the kingdom, which severed diplomatic and economic ties with the country.

Saudi Arabia then moved to withdraw all 12,000 of its students in Canada, with the intention of transferring them and their families to other English-speaking nations with high-quality universities and "good relations" with Saudi Arabia.

New Zealand is on that short list. It hosts over 2000 Saudi students, the New Zealand Ministry of Foreign Affairs and Trade (MFAT) told Newshub last week.