Japan, South Korea, Turkey, India and China will face pressure to eliminate Iranian oil imports as the US eliminates sanctions waivers in an effort to increase pressure on Tehran one year after Washington left the Iran nuclear deal.

A senior US official told the Financial Times that Michael Pompeo, US secretary of state, would on Monday announce a move to end waivers when they expire in early May. The move is just the latest effort to ratchet up pressure on Iran. Earlier this month, the US took the unprecedented step of branding Iran’s Revolutionary Guard a foreign terrorist organisation, the first time formally labelling part of a foreign government as terrorists.

The end of waivers comes as oil prices have risen sharply this year, reaching highs above $72 a barrel due to voluntary and involuntary cuts by Opec members that have tightened supply. The market is also watching closely for further losses from turmoil in Venezuela and Libya. The decision was first reported by the Washington Post.