On Monday, January 11th, Iran’s Revolutionary Guards Corps seized a South Korean tanker owned by Taikun Shipping Co. Ltd. and detained its crew. In response, South Korea is sending a delegation to Iran.

According to Iranian state news agencies, the South Korean ship was detained because it was polluting the Persian Gulf and the Strait of Hormuz. The ship was carrying 7,200 tons of chemicals, mostly methanol, according to Taikun Shipping Co. Ltd. The company denies, however, that it was polluting the waters and pointed out that if the ship were violating environmental rules, the coast guard, not soldiers, was supposed to approach the ship. Instead, according to the captain of the ship, armed soldiers approached the crew and without explanation demanded that the ship head for Iranian waters. The captain has since been unreachable, and security cameras on the ship’s deck have been turned off.

Aboard the ship are 20 crew members, five from South Korea, 11 from Myanmar, two from Indonesia, and two from Vietnam, according to Choi Young-sam, a spokesman for the South Korean Foreign Ministry.

The seizure came just two weeks before President-elect Joe Biden takes office in the United States and days before South Korea had planned a visit to Tehran, the Iranian capital. Officials expected to discuss the frozen Iranian assets in South Korean banks during this visit. These assets, which total $7 billion in Iranian funds, became inaccessible to Iran after President Trump withdrew the US from the Iran nuclear accord.

After withdrawing from the accord in 2018, President Trump reinstituted maximum financial sanctions on Iran. Nations still participating in the accord along with some US Democrats have been pushing for Joe Biden to re-join the agreement. The timing of the seizure has elicited accusations from the US State Department that Iran is using the ship as leverage to “extort the international community into” unfreezing the $7 billion held in banks. The Iranian government hopes to access these funds and use them to purchase COVID-19 vaccines.

Tilak Doshi, a visiting senior fellow at Middle East Institute, National University Singapore said the incident provided an example of Iran’s desire to show its strength as US President-elect Joe Biden prepares to take office, and that the frozen assets would likely be raised by Iran during talks with Seoul. Tilak said that there is no doubt that “release of the funds by South Korea will be the key demand on the Iranian side,” in negotiating for the release of the tanker.

Not only does the seizure of the tanker have implications for US sanctions on Iran and North Korean-Iranian relations, but the seizure also heightens tensions over Iran’s nuclear program and the first anniversary of the killing of Gen. Qassem Soleimani, Iran’s top military leader, in a US drone strike. In fact, the same day the tanker was seized, Tehran said it had resumed 20% uranium enrichment at its underground Fordow nuclear facility – a breach of a nuclear deal Iran signed in 2015, among other world powers.

Ali Rabiei, an Iranian government spokesman, strongly denied any suggestions that the seizure was a form of “hostage-taking” linked to Iranian funds being held by South Korea. “If anybody is to be called a hostage-taker, it is the South Korean government that has taken our more than $7 billion hostages under a futile pretext,” Rabiei told reporters at a news conference.

Foreign Minister Kang Kyung-Wha of South Korea wouldn’t comment on the possibility of Iran using the seizure as leverage in the negotiations. She said “we need to verify the facts first and ensure the safety of our crew,” according to BBC. Last Tuesday, Choi Young-sam stated that a delegation will be dispatched to Iran “in the earliest possible time” to negotiate for an early release of the ship.

South Korea’s foreign ministry has since invited the Iranian ambassador to Seoul to resolve the seizure. When 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.” Meanwhile, the South Korean Defense Ministry released a statement that it is dispatching an anti-piracy unit consisting of a warship and 300 troops to the Strait of Hormuz.