Supreme Leader of Iran Ayatollah Ali Khamenei supported the proposal of the President of the country Hassan Rouhani on blocking oil supplies. "If the export of Iranian oil is blocked, then no other country in the region will also export it," Khamenei said in a statement posted on his website on Saturday, July 21.

Khamenei also called on the head of the Iranian Foreign Ministry to strictly follow the president's position on this issue. Rouhani previously threatened to cut off oil supplies to the international market through the Strait of Hormuz in the event that the US will seek to stop the purchase of Iranian oil by other countries.

Through the Strait of Hormuz the Persian Gulf joins the Gulf of Oman, and further with the Arabian Sea and the Indian Ocean. Bahrain, Qatar and Kuwait can supply oil for export only through this strait, since they do not have other exits to the sea. Through it also go tankers of Saudi Arabia, the United Arab Emirates and Iraq.

In total, about a fifth of the world's oil exports pass through the Strait of Hormuz, a large part of it goes to China, Japan, India, South Korea and Singapore.

In early May, President Donald Trump announced the withdrawal of the United States from the Joint Comprehensive Plan of Action (SWDP), concluded between Iran, the United States, Russia, China, Britain, France and Germany in 2015 and envisaging Tehran's implementation of a number of steps to limit its nuclear program to exchange for cancellation of sanctions. The remaining parties to the agreement criticized Trump's decision and announced their intention to keep the agreements in force.

After the withdrawal from the agreement, the US extended sanctions against Iran, and then demanded from the Allies to no longer buy oil from Iran on November 4, saying they would otherwise impose sanctions against buyers.

So, the US sent warnings to a number of Japanese companies with a demand to reduce the purchase of oil from Iran to zero.

After that, it became known that Japan is considering the possibility of renouncing Iranian oil and at the same time beginning negotiations in order to withdraw its companies from possible US sanctions, and is also looking for a substitute for Iranian oil in the markets of the UAE and Saudi Arabia.