The United States moved forward Monday with a naval blockade aimed at restricting maritime traffic to and from Iranian ports through the Strait of Hormuz, following President Donald Trump’s pledge to put an end to what he described as Tehran’s “extortion” of countries relying on the key global shipping route.

US Central Command, headquartered in Tampa, Florida, said the operation would be carried out “impartially,” clarifying that ships traveling to or from ports outside of Iran in the Persian Gulf would be allowed to proceed without interference.

Shipping activity in the strategic waterway has slowed significantly in recent days. Data from the analytics platform Kpler showed that 14 vessels passed through the strait on Sunday, with even fewer ships entering or leaving in the days following the announcement of a two-week cease-fire between Washington and Tehran.

President Trump revealed the blockade decision on Sunday in a Truth Social post, declaring: “THIS IS WORLD EXTORTION, and Leaders of Countries, especially the United States of America, will never be extorted.”

He continued by warning, “No one who pays an illegal toll will have safe passage on the high seas,” referencing reports that Iran has attempted to impose fees of up to $2 million per oil tanker for transit through the strait.

Energy markets reacted quickly to the developments, with crude oil prices climbing back above $100 per barrel after US-Iran negotiations collapsed over the weekend in Pakistan.

Wall Street also saw an immediate impact at the opening bell, as the Dow Jones Industrial Average dropped 0.7% and the S&P 500 declined by 0.3%.

Israeli Prime Minister Bibi Netanyahu cautioned that the current cease-fire with Iran remains unstable, warning it “could turn on a dime,” according to multiple reports.

Vice President JD Vance later briefed Netanyahu on the discussions held in Islamabad, Pakistan, concluding that the United States “could not tolerate Iran’s blatant violation of the agreement to enter negotiations.”

Speaking during a cabinet meeting on Monday, Netanyahu said that Vance emphasized the administration’s central objective of “removing all enriched material and ensuring that there will be no enrichment in the coming years.”

Netanyahu also dismissed speculation of disagreements between Jerusalem and Washington, stating, “The claims that there is a rift between us are completely false.” He added, “The exact opposite is true. Anyone who was present in these conversations, and in the daily discussions we hold with the president and his team, can attest to that.”