Iran’s parliament has approved the closure of the key oil shipping route Strait of Hormuz after the US bombed three of its nuclear facilities. Iranian state media today reported that the final decision will be taken by the Supreme National Security Council.

The Strait of Hormuz is one of the world’s most critical choke points, through which a fifth of global oil and a third of the world’s liquefied natural gas supply flows. So far, most experts had agreed that Iran would not go that far to close the strait but US actions this morning seemed to have changed that.

The strait connects the Persian Gulf to the Arabian Sea and the Indian Ocean. The narrow channel, approximately 33 km wide at the narrowest point, separates Iran from the Arabian Peninsula. The shipping lanes in the waterway are even narrower to three kilometer wide in each direction, making them vulnerable to attacks and threats of being shut down, which Iranian Parliament has decided to do now.