FRANKFURT, Germany (AP) — Global oil prices are climbing in the wake of the U.S. move to impose sanctions on countries that buy Iranian oil.

And analysts said Tuesday that prices could keep heading higher.

The U.S. announced the sanctions last year to push Iranian leaders to renegotiate an agreement aimed at keeping them from developing nuclear weapons. But some countries got temporary waivers that allowed them to import Iranian oil. The U.S. now says those waivers expire May 2.

Among those affected are China, India, Japan, South Korea and Turkey. U.S. Secretary of State Mike Pompeo said Monday the U.S. is counting on ally Saudi Arabia to ensure sufficient supply.

New York Mercantile Exchange rose 10 cents to $65.65 per barrel while international Brent crude rose 14 cents to $74.18 per barrel.