Iran agreed on Tuesday to free the 19 crew members of a South Korean oil tanker that was seized a month ago, but it is uncertain when the sailors will return home. 

Tehran has not yet released the ship or its captain, who is to remain in Iranian custody until the investigation into what the country has described as a breach of its environmental pollution laws is completed.
 
According to the operator of the MT Hankuk Chemi, at least 13 sailors are required to be on board the tanker for it to operate safely. That means it would be difficult for any crew members to leave until all are released. 

The Korean Foreign Ministry said it is in consultations with the vessel operator to figure out the logistics and determine how many sailors can leave. 

“Iran hasn’t presented the exact time frame on (when it will complete the judicial process),” a ministry official said. “We are urging for the prompt release of the vessel through a swift and fair process.” 

The two countries had been in tough negotiations since Jan. 4, when Iran’s Islamic Revolutionary Guard Corps seized the oil tanker and its 20 sailors -- 11 from Myanmar, five Koreans, two Indonesians and two Vietnamese -- in the Persian Gulf, citing “environmental and chemical pollution concerns.”

Iranian Foreign Ministry Spokesperson Saeed Khatibzadeh said Tuesday that the country had decided to allow the crew members to leave Iran in a “humanitarian move,” following the Korean government’s request. He added that the legal investigation into the tanker would continue. 

Korea’s Foreign Ministry said the decision to release the sailors came during a phone conversation Tuesday evening between Vice Foreign Minister Choi Jong-kun and his Iranian counterpart, Deputy Foreign Minister Seyyed Abbas Araghchi. 

For weeks, the two countries have been discussing conditions for the release, as well as billions of dollars of Iranian funds frozen in Korean banks due to sanctions imposed by the US. 

Tensions have been simmering between Seoul and Tehran over about $7 billion in revenue from oil sales frozen in Korean banks since 2019 due to sanctions reimposed on Iran by the Donald Trump administration, after Washington’s unilateral decision to withdraw from the 2015 nuclear accord.

The timing of the seizure, which arrived as Tehran doubled down pressure to release the Iranian money, has raised speculation that the ship was seized to gain leverage to unlock the frozen assets here. But Iran denied that was the case.

Choi promised Araghchi that he would pursue “speedy” action to unlock the funds, and would talk with the US about matters that require consultations.

Earlier last month, the vice foreign minister visited Tehran to discuss both the tanker and the funds.

By Ahn Sung-mi (sahn@heraldcorp.com)