A routine flight to Washington has turned into a diplomatic question for Canada. When Israeli Prime Minister Benjamin Netanyahu flew to the United States on Monday, he flew over Canada to get there.
The aircraft that carried him is well known. The flight path of the Israeli government Boeing 767, known as the Wing of Zion, took the plane across Canadian territory.
What makes the route sensitive is a standing legal threat. Prime Minister Mark Carney has said he would honour the International Criminal Court's arrest warrant for Netanyahu if he came to Canada.
Netanyahu never touched down, but the overflight itself raised a question. It is unclear whether the Canadian government gave permission for his plane to use Canadian airspace.
There is a formal process for such flights. The government's own website says applications for foreign state military or scientific aircraft to operate within Canadian territory should be submitted at least 72 hours, or three working days, before the proposed date of entry into Canadian airspace.
The Israeli side says it followed that step, up to a point. The Israeli government said it had sought permission from Canada for Netanyahu to enter Canadian airspace, but did not respond when asked whether Canada had actually granted it.
On the Canadian side, officials would not clear up the uncertainty. A spokesperson for the Prime Minister's Office declined to say whether Canada granted permission, and Global Affairs Canada also declined, saying it would not comment on the route chosen by the Israeli leader.
For at least one legal expert, the silence is not the end of the matter. An international law professor said that either way, the overflight undermines international law and also Canadian sovereignty.