The United States has imposed additional sanctions against Iran targeting 35 entities and vessels that it says are part of a “shadow fleet of vessels” transporting cargoes of Iranian petroleum to foreign markets.

The sanctions came in response to Iran’s October 1 attack against Israel and to its announced nuclear escalations, the US Department of Treasury highlighted.

Such sanctions target key sectors of Iran’s economy with the aim of denying the government funds to support its nuclear program and develop advanced drones and missiles.

Petroleum revenues provide the Iranian regime with the resources to fund its nuclear program, develop advanced drones and missiles, and provide ongoing financial and material support for the terrorist activities of its regional proxies, the Treasury Department noted.

“Iran continues to funnel revenues from its petroleum trade toward the development of its nuclear program, proliferation of its ballistic missile and unmanned aerial vehicle technology, and sponsorship of its regional terrorist proxies, risking further destabilizing the region,” Acting Under Secretary for Terrorism and Financial Intelligence Bradley T. Smith said in a statement.

“The United States remains committed to disrupting the shadow fleet of vessels and operators that facilitate these illicit activities, using the full range of our tools and authorities,” Smith added.

The Treasury Department’s statement said, “Iran relies upon a sprawling network of tankers and ship management firms in multiple jurisdictions to transport its petroleum to overseas customers.”

This includes tactics, it said, such as “false documentation, manipulation of vessel tracking systems, and constant changes to the names and flags of vessels.”

The latest sanctions will freeze the entities’ assets in the US and generally make it illegal for Americans to engage in financial transactions with them.