Canadian Foreign Minister Mélanie Joly called on Wednesday for a full investigation into the killing of aid workers in the Gaza Strip, including a Canadian citizen, in an Israeli airstrike.

She said on the sidelines of a NATO foreign ministers meeting in Brussels that Israel must respect international law.

Seven aid workers were killed in the attack that took place on Monday, including Jacob Flinker, 33, who holds both American and Canadian citizenship.

In Toronto, Prime Minister Justin Trudeau said officials spoke to Israeli Ambassador Ido Mod to express "our strong dismay at the unacceptable killing of several aid workers, one of whom holds dual Canadian and American citizenship... The world needs very clear answers about how this happened."

Israel says the airstrike that killed the seven aid workers was accidental.