US President Donald Trump has again shared an image on social media depicting the strategically vital Strait of Hormuz as 'NEW US Territory', drawing a sharp rebuke from Iran's top security official as Washington prepares to announce major new economic sanctions on Tehran.

Escalating Rhetoric Over a Vital Waterway

Trump's latest post on Truth Social, described by multiple reports, repeats a claim he first made on August 18 and follows his August 14 statement at a police academy in Long Island that "Pretty soon I'll be declaring the Strait of Hormuz a territory of the United States." According to CNBC, Trump told reporters he views the waterway as "American territory right now."

Iran's Supreme National Security Council Secretary Mohsen Rezaei dismissed the claim, saying the gap between America's inability to reopen the strait and its claim to own it was "greater than the 7,000-mile distance between Washington and the Strait itself." He added, "Welcome to the post-American order in the Persian Gulf."

A New Economic Front

The exchange came as US Treasury Secretary Scott Bessent is expected to announce on Monday what he has described as "the toughest sanctions in history" against Iran. Bessent has characterized the coming measures as an "economic D-Day," a term he used in a Financial Times opinion piece in which he wrote, "At dawn begins an economic D-Day - the single greatest financial offensive ever marshalled against an adversary," as reported by The Canberra Times.

The new measures would add to an extensive sanctions regime already targeting Iran's banking, energy, aviation, and cryptocurrency sectors, according to CNBC. The same outlet reported that Bessent warned that "any nation that serves as a financial artery of a withering regime should expect to share in its isolation."

Iranian Foreign Ministry spokesman Esmaeil Baghaei said the planned secondary sanctions "find no foundation in international law" in a post on X.

Hormuz Traffic Surges Despite Tensions

Despite Iran's insistence that the strait remains closed, shipping traffic through the waterway has surged dramatically. Nearly 200 ships navigated the strait last week, up from about 150 the previous week and just 40 two weeks earlier, according to data from the UK Maritime Trade Operations centre cited by multiple outlets.

Kurdistan24 reported that the Omani route—backed by the US and authorized by the International Maritime Organization—has been key to the increase, with more than 80 percent of liquid cargoes using it or going 'dark' over the past two weeks, according to data from maritime intelligence firm Kpler. However, Reuters reported that the route is rejected by Iran.

Homayoun Falakshahi, head of crude oil analysis at Kpler, said the data increasingly suggested Iran had only partial control over the strait. Dan Pickering of Pickering Energy Partners said the Omani route made sense for vessels seeking to avoid paying a toll to Tehran.

Despite the surge, traffic through the strait remains about 90 percent below pre-war levels, according to the UK Maritime Trade Operations, as reported by The Nation (Pakistan).

Warnings of Broader Conflict

Rezaei has warned that any country that joins US economic pressure "will be regarded by us as an enemy" and that Tehran would first negotiate with such countries before striking their interests. In an interview with Iran's state broadcaster, he said that if surrounding countries choose to join a US siege, Iran "will not let even a single drop of oil be exported from the Strait of Hormuz"—a warning also repeated in comments to other nearby states.

Iranian Foreign Minister Abbas Araghchi dismissed the effectiveness of US economic warfare, listing past failed US measures in a post on X. "14 years ago: 'Most crippling sanctions in history.' Failed. 8 years ago: 'Maximum pressure.' Failed. 5 months ago: 'Unconditional surrender.' Failed. Today: 'Most crushing economic operation ever.' Bound to fail."

A Narrowing Window for Diplomacy

A 60-day period to reach an agreement between the US and Iran expired on Monday without a deal, according to multiple reports. President Masoud Pezeshkian has called for an end to the war and defended earlier negotiations with Washington, The National reported.

Beijing has called for diplomacy and opposed unilateral pressure, but Washington has urged China—which Kpler data shows buys more than 80 percent of Iran's seaborne oil—to cooperate. Iranian Central Bank Governor Abdolnaser Hemmati said last week that the country's oil exports had effectively fallen to zero.