IRGC warns ships off Oman's corridor in Hormuz as Rubio draws line on tolls

Iran's Islamic Revolutionary Guard Corps (IRGC) warned on Thursday that all vessels transiting the Strait of Hormuz must use routes designated by Tehran and that any ship navigating outside those routes is doing so illegally, directly challenging Oman's announcement of a new temporary corridor running close to its own coast.

"All parties are hereby informed that the only authorized routes for passing through the Strait of Hormuz are those announced by the Islamic Republic of Iran," the IRGC said in a statement. "Navigation outside these designated routes is highly dangerous and prohibited." The statement added that a route announced hours earlier – which matched Oman's proposed corridor – was "unacceptable and completely dangerous" and had been decided on without prior coordination with Iran. "Violators will be dealt with," it warned without elaborating.

IRGC-affiliated media claimed three oil tankers using Oman's southern corridor had turned back into the Persian Gulf after receiving warnings from the IRGC Navy. South Korea's Oceans Ministry said separately that five South Korean-operated vessels had successfully exited the strait on Thursday, indicating traffic was still moving.

Iran's parliament National Security Commission secretary Benyamin Saeedi said control of the waterway was "fully and firmly in the hands of Iran's military forces" and warned that "any miscalculation in this maritime area will be met with a decisive response." He said Iran expected the US to demonstrate compliance with the framework deal in practice rather than in statements.

US Secretary of State Marco Rubio, speaking at a GCC ministerial meeting in Bahrain on Thursday, said Washington would not accept any fees or tolls under any description. "You can call it a toll, you can call it a fee, at the end of the day it's all semantics," Rubio said. He further stated no country owns the Strait of Hormuz and therefore no country has the right to charge for its use.

Despite the competing claims, shipping data from the International Maritime Organisation showed a gradual normalisation of traffic. A total of 13 vessels transited on Tuesday, 32 on Wednesday, and 12 by Thursday morning. Last week, 125 vessels crossed the strait, up from 33 the week before, according to data from Lloyd's List Intelligence. Oil markets continued to ease, with Brent crude falling to its lowest level since 27 February.