OTTAWA (AP) — Iran has ordered Canada's ambassador to leave the country, the Canadian foreign minister said late Monday, calling the move entirely unjustifiable.

Foreign Affairs Minister Maxime Bernier suggested the expulsion of Ambassador John Mundy, who was recently appointed and yet to have his credentials accepted, was a tit-for-tat move by the government in Tehran.

Canada and Iran have tried to come to an agreement on an exchange of ambassadors for some time, but Canada is not willing to accept the candidates Tehran has proposed thus far.

"Unfortunately, we have as yet been unable to accept the candidates Tehran has submitted," Bernier said in a statement. "We believe that the expulsion of our ambassador is an unfortunate and unjustified consequence of this situation. As always, Canada remains prepared to receive an Iranian ambassador provided a suitable candidate is presented," he said.

The diplomatic slap came one day after the Iranian charge d'affaires expressed frustration that his country's overtures to Canada were being ignored by the Canadian government.

Seyed Mahdi Mohebi said in an interview with The Canadian Press that he has twice asked for a resumption of high-level contacts up to the foreign minister level.

Relations have been frosty since former Canadian ambassador Ken Taylor helped spirit Americans out of the U.S. Embassy in 1980 before they could be taken hostage shortly after the Iranian revolution.

Bernier said the Canadian Embassy in Iran now will be headed by the charge d'affaires. Both countries will continue to maintain embassies in the respective capitals and conduct normal operations, the release said