TEHRAN: Iran's Revolutionary Guards said yesterday it had seized a South Korean-flagged tanker in Gulf waters for breaking "maritime environmental laws". "A ship owned by South Korea was seized by our force's (navy) this morning," the Guards said on its website Sepahnews. "This tanker was headed from Saudi Arabia's Al Jubail port and was seized due to the repeated infringement of maritime environmental laws," it added. It identified the ship as the South Korean-flagged Hankuk Chemi, which it said was carrying 7,200 tons of "oil chemical products".

South Korea's foreign ministry yesterday demanded the "early release" of the oil tanker. "The foreign ministry… is demanding an early release of the vessel," it said in a statement, adding that it had confirmed the safety of the tanker's crew. Seoul dispatched its anti-piracy unit to the Gulf immediately after receiving reports the ship had been seized, according to the defense ministry.

News of the seizure comes amid renewed regional tensions particularly as Iran marks the first anniversary of the assassination of its revered commander Qasem Soleimani in a US drone strike in Jan 2020. Tehran yesterday also announced it had started the process to enrich uranium to 20 percent purity at its underground Fordo facility, state media reported, in a move which drew swift international concern.

It is the latest and most important suspension of nuclear commitments by Iran under a landmark 2015 deal, starting in 2019, and in response to US President Donald Trump's dramatic withdrawal from the accord in May 2018, with the US imposing crippling economic sanctions on Tehran.

"The process for producing 20 percent enriched uranium has started at Shahid Alimohammadi enrichment complex (Fordo)," government spokesman Ali Rabiei said, quoted on the website of the state broadcaster. According to the official, President Hassan Rouhani ordered the enrichment "in recent days", and "the gas injection process started as of hours ago".

The UN nuclear watchdog confirmed yesterday that Iran had started the process of enriching uranium to 20 percent. "Iran today began feeding uranium already enriched up to 4.1 percent U-235 into six centrifuge cascades at the Fordo Fuel Enrichment Plant for further enrichment up to 20 percent," a statement from the International Atomic Energy Agency (IAEA) said.

The statement added that "IAEA inspectors were present at the site to detach the Agency's seal from a cylinder with the feed material" and that "the cylinder was then connected to the feeding line to start the production of uranium enriched up to 20 percent". A total of 1,044 IR-1 centrifuges were being used in the process, the IAEA said.

The European Union yesterday said that Iran's enrichment program would be a "considerable departure" from deal. Israeli Prime Minister Benjamin Netanyahu reacted angrily to the news of enrichment. "Iran's decision to continue violating its commitments, to raise the enrichment level and advance the industrial ability to enrich uranium underground, cannot be explained in any way except as the continued realization of its intention to develop a military nuclear program," Netanyahu said in a statement yesterday. "Israel will not allow Iran to manufacture nuclear weapons."

The seizure of the South Korean-flagged tanker came at the request of Hormozgan Province's maritime organization and upon the order of the provincial prosecutor, Sepahnews said. The arrested crew were from South Korea, Indonesia, Vietnam, and Myanmar, the Guards said, without giving further details. A photo released by the website appeared to show three speedboats and a patrol boat approaching the tanker. The Guards' statement did not specify where was the tanker was seized or transferred to.

The British body, United Kingdom Maritime Trade Operations, said in a message that there had been "an interaction" in the Strait of Hormuz between a merchant vessel and Iranian authorities early yesterday, which had caused the ship to "make an alteration of course North and … into Iranian waters". Fars news agency had earlier reported that the ship "has been seized in Persian Gulf waters (…) and transferred to our country's ports."

Meanwhile, the US reversed a decision to bring an aircraft carrier home from the Gulf Sunday, with the Pentagon saying that due to "recent threats" by Iran the USS Nimitz would stay in position. The Nimitz has been patrolling Gulf waters since late November, but in a statement issued on Dec 31, acting US defense secretary Christopher C Miller ordered the vessel to "transit directly home to complete a nearly 10-month deployment".

The New York Times, quoting US officials, said this move was part of a "de-escalatory" signal to Tehran to avoid a conflict in President Donald Trump's last days in office. However, Miller issued a new statement changing course on Sunday. "Due to the recent threats issued by Iranian leaders against President Trump and other US government officials, I have ordered the USS Nimitz to halt its routine redeployment," he said. "The USS Nimitz will now remain on station in the US Central Command area of operations. No one should doubt the resolve of the United States of America." He did not elaborate on the threats involved. - Agencies