Iran has closed the Strait of Hormuz again, after briefly reopening it earlier this week. The Islamic Revolutionary Guard Corps Navy said it will stay shut until the US lifts its blockade on Iranian ports.

The closure followed fresh attacks on shipping. The UK Maritime Trade Operations said a tanker and a container ship were attacked off Oman — the first such attacks in more than ten days. India’s foreign ministry said two Indian-flagged ships were involved in a “shooting incident” in the strait.

The Wall Street Journal reported that Iran and its Houthi allies struck an oil and chemical tanker near Qatar late Wednesday, causing casualties, followed by Houthi strikes in Riyadh on Thursday — the third straight day of attacks on the Saudi capital.

Trump said the US was having “very good conversations” with Iran but would not be “blackmailed” over the waterway. The strait carried about 20 percent of global oil and fuel shipments before the war.