A South Korean delegation is heading to Iran on Wednesday to negotiate the release of a seized tanker and its crew, Yonhap news agency reported.

A South Korean chemical tanker was seized by Iran's Revolutionary Guards on Monday in waters off Oman over environmental violations claimed by Iranian authorities, an allegation denied by the ship's operator. 

Iran denied on Tuesday it was using the ship and its crew as hostages for Iran's $7 billion in funds frozen in South Korean banks due to U.S. sanctions. 

(Cover: Picture posted by Iran's semi-official Tasnim news agency showed Islamic Revolutionary Guards Corps boats escorting the South Korean-flagged vessel. /Reuters)