South Korea’s oceans minister is opposed to Iran’s reported move to impose fees on ships passing through the strategically vital Strait of Hormuz, calling the action a violation of international law, media reports said Friday, Anadolu reports.

Speaking at a news conference in the southeastern port city of Busan, Hwang Jong-woo said the waterway is an international shipping route where free navigation must be guaranteed, according to Yonhap News.

“Charging shipping tolls in the strait is practically equivalent to blocking the waterway,” said Hwang, adding that, unlike the man-made Suez Canal, the Strait of Hormuz consists of international waters protected under international agreements.

On Wednesday, Iran’s parliamentary National Security and Foreign Policy Commission head Ebrahim Azizi said a strategic proposal on the “smart management” of the strait has reached its final stage, which has been uploaded to parliament’s system for review and approval. He added that the proposal aims to use Iran’s geographic position in the strategic waterway as a “power-generating leverage.”

Hwang said South Korea is temporarily rerouting some oil tankers through the Red Sea as uncertainty continues about the reopening of the Hormuz route. The ministry said four South Korean vessels have successfully returned via the Red Sea, while 26 Korean ships carrying 158 sailors remain stranded in the Strait of Hormuz.