In this photo released on Jan 4, 2021, by Tasnim News Agency, the MT Hankuk Chemi, a South Korean-flagged tanker, is seen escorted by Iranian Revolutionary Guard boats on the Persian Gulf. (PHOTO / TASNIM NEWS AGENCY VIA AP)

SEOUL/TEHRAN - South Korea is dispatching a delegation to Iran as early as today to seek the release of a tanker seized in Gulf waters by Iranian forces, with a senior diplomat set to go ahead with a planned visit Tehran on Sunday amid tensions over US$7 billion in Iranian funds frozen in South Korean banks due to US sanctions.

Seoul confirmed the seizure of a South Korean chemical tanker by Iranian authorities in the waters off Oman, and demanded its immediate release.

Asked about the status of the ship’s crew before his meeting at the Seoul foreign ministry, Iranian ambassador Saeed Badamchi Shabestari told reporters “all of them are safe”

An Iranian government spokesman on Tuesday rejected allegations that Iran’s seizure of the South Korean-flagged tanker amounted to hostage-taking, and said it was Seoul that was holding US$7 billion of Iran’s funds “hostage”.

“We’ve become used to such allegations ... but if there is any hostage-taking, it is Korea’s government that is holding US$7 billion which belongs to us hostage on baseless grounds,” spokesman Ali Rabiei told reporters at a news conference streamed live online.

Seoul’s foreign ministry called in the Iranian ambassador to South Korea for a meeting and urged the early release of the tanker and its crew of 20. It was carrying a cargo of more than 7,000 tonnes of ethanol when it was seized on Monday over what Iranian media said were pollution violations.

Asked about the status of the ship’s crew before his meeting at the Seoul foreign ministry, Iranian ambassador Saeed Badamchi Shabestari told reporters “all of them are safe”.

Iranian state TV previously cited a Tehran government official as saying South Korea’s Vice-Foreign Minister Choi Jong-kun had been scheduled to visit before the seizure of the tanker Hankuk Chemi to discuss Iran’s demand that the frozen funds be released.

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Choi will discuss “various pending issues” between the two countries on top of the seizure, Foreign Ministry spokesman Choi Young-sam said at a briefing in Seoul on Tuesday.

“In the earliest possible time, a working-level delegation led by the regional director will be dispatched to Iran to try to resolve the issue on the ground through bilateral negotiations,” spokesman Choi said.

Iran said that the seizure of the Hankuk Chemi was a "normal" procedure over a "technical matter"

Earlier in the day, South Korea's Foreign Minister Kang Kyung-wha said that she was making diplomatic efforts to secure the release of the seized tanker, Yonhap news agency reported.

Kang said she responded to her counterparts in Iran on Monday and the ministry was in talks with diplomats in Tehran and Seoul to resolve the issue, Yonhap reported.

Asked about Iran’s intentions for the frozen assets, Kang said the safety of the ship’s crew was more important, Yonhap reported.

Iran’s Revolutionary Guards Corps (IRGC) seized the tanker in Gulf waters and detained its crew, Iranian media reported on Monday. 

Iranian state television quoted Saeed Khatibzadeh, a Foreign Ministry spokesman, as saying the ship had been seized for “polluting the sea”.

READ MORE: Iran seizes S. Korean tanker over 'environmental breach’

Iran said that the seizure was a "normal" procedure over a "technical matter".

"Like other countries, Iran is sensitive to this kind of violations, especially to the pollution of the marine environment, and deals with it within the framework of the law," Khatibzadeh was quoted as saying by the official news agency IRNA.

Ismail Makizadeh, deputy director for Maritime Affairs at PMO in Hormozgan province, told IRNA that the Hankuk Chemi was seized by the IRGC over suspected seawater pollution

According to first reports from local officials, the cause of the seizure of the Hankuk Chemi was a "very technical issue" and not extraordinary in nature, Khatibzadeh said.

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On Monday evening, Massoud Polmeh, secretary of the Shipping Association of Iran, said that the Hankuk Chemi was responsible for "repeated violations of environmental laws," and must pay compensation for the damage to the environment, according to the official website of Iran's Ports and Maritime Organization (PMO).

Meanwhile, Ismail Makizadeh, deputy director for Maritime Affairs at PMO in Hormozgan province, told IRNA that the Hankuk Chemi was seized by the IRGC 17.7 kilometers from Iran's Greater Tunb island over suspected seawater pollution.

An IRGC naval patrol noticed the vessel's violation and warned it, but the vessel continued on its way without heeding the warnings, Makizadeh said.

According to the official, the tanker was confiscated on the orders of the provincial judicial authority, and was then directed to the port of Bandar Abbas for the necessary investigations and legal procedures.

The ship’s Busan-based operator, Taikun Shipping Co Ltd, told Reuters there was nothing to indicate before the seizure of the vessel that Iranian authorities were probing possible violations of environmental rules.

“If it really was marine pollution, as they (Iranian media) say, the coast guard was supposed to approach the ship first,” Taikun’s management director Lee Chun-hee said by telephone. “But instead, armed soldiers approached the crew and said they needed to be investigated.”

Last Sunday, the Tehran Times newspaper reported Iran was hoping to negotiate an agreement to use the frozen funds to trade for commodities, including coronavirus vaccine doses.

According to South Korean news agency Yonhap, a foreign ministry official said the Iranian government had tried to secure vaccines through the global COVAX initiative, backed by the World Health Organization. Tehran had been in talks with the ministry and the US Treasury to pay for the doses with South Korean won.