U.S. President Donald Trump's administration temporarily exempted Japan and seven other parties from its ban on Iranian oil imports as it reimposed sanctions against Tehran on Monday.

The seven others are China, India, South Korea, Italy, Greece, Taiwan and Turkey, Secretary of State Mike Pompeo said at a joint news conference with Treasury Secretary Steven Mnuchin.

Earlier Monday, the administration reimposed sanctions on Iran's energy, banking, shipbuilding and shipping sectors to compel Tehran to end its nuclear program and support for militant groups in the Middle East.

Referring to the waivers, Pompeo said the administration will continue negotiations with the eight parties to end oil imports from what it calls the world's largest state sponsor of terrorism.

"Iran will never come close to getting a nuclear weapon on President Trump's watch," he said, vowing to step up the U.S.-led campaign of economic pressure against Tehran.

Two of the eight parties will wind down Iranian oil imports to zero in "weeks" and the six others will import "at greatly reduced levels," Pompeo said Friday.

Japan had asked for a waiver during negotiations with the United States, saying its imports of Iranian oil have been recently falling.

Takashi Tsukioka, president of the Petroleum Association of Japan, said in September that Japanese oil distributors would temporarily suspend oil imports from Iran until the end of the negotiations.

Aside from restrictions on oil imports, the administration added more than 700 names -- including individuals, entities, vessels and aircraft linked to the energy and financial sectors and other segments of Iran's economy -- to the U.S. list of sanctioned entities.

Of those added, more than 300 are new designations and the remainder won sanctions relief under the 2015 Iranian nuclear deal, from which Trump withdrew the United States in May.

At Washington's urging, SWIFT, the global messaging network that connects the world's financial institutions, said it is suspending its service for some unspecified Iranian financial institutions.

"In keeping with our mission of supporting the resilience and integrity of the global financial system as a global and neutral service provider, SWIFT is suspending certain Iranian banks' access to the messaging system," it said in a statement.

"This step, while regrettable, has been taken in the interest of the stability and integrity of the wider global financial system," it added.

Mnuchin had warned that Brussels-based SWIFT would be subject to U.S. sanctions if it provided financial messaging services to such institutions.

After pulling the United States out of the deal struck between Iran and six major powers -- Britain, China, France, Germany, Russia and the United States -- the administration began reimposing sanctions on the Islamic Republic in August.

Under the deal, Tehran had agreed to curb its nuclear activities in exchange for the lifting of crippling economic sanctions.