The United States reimposes oil and financial sanctions against Iran on Monday, significantly turning up the pressure on Tehran in order to curb its missile and nuclear programs and counter its growing military and political influence in the Middle East.

The move will restore U.S. sanctions that were lifted under a 2015 nuclear deal negotiated by the administration of President Barack Obama, and add 300 new designations in Iran's oil, shipping, insurance and banking sectors.

President Donald Trump announced in May that his administration was withdrawing from what he called the "worst ever" agreement negotiated by the United States. Other parties to the deal, including Britain, France, Germany, China and Russia, have said they will not leave.

Details of the sanctions will be released at a news conference scheduled for 8:30 a.m. EST (1330 GMT) with Secretary of State Mike Pompeo and Treasury Secretary Steven Mnuchin.

China, India, South Korea, Japan and Turkey — all top importers of Iranian oil — are among eight countries expected to be given temporary exemptions from the sanctions to ensure crude oil prices are not destabilized.

The countries will deposit Iran's revenue in an escrow account, U.S. officials have said.