(Bloomberg) -- The U.S. Treasury Department imposed sanctions on a raft of Iranian companies on Tuesday, including a steel producer, tractor manufacturer and banks.

Treasury’s Office of Foreign Assets Control announced the sanctions on its website without disclosing why the companies were being excluded from the U.S. financial system. Companies including Bank Mellat, Mehr Eqtesad Bank, Iran Tractor Manufacturing Company and Mobarakeh Steel Company were on the list.

The U.S. is seeking to choke off Iran’s economy with expansive sanctions against the country’s oil industry that take effect in November. Trump withdrew from the seven-nation Iran nuclear deal in May, dismissing objections from the other countries in the accord.

The Trump administration hopes re-imposing sanctions on the Islamic Republic will force its leaders back to the negotiating table to agree on a new, broader pact that would constrain not only its nuclear program but also what the U.S. calls its “malign activity” in the Middle East and its development of ballistic missiles.

To contact the reporters on this story: Nick Wadhams in Washington at nwadhams@bloomberg.net;Saleha Mohsin in Washington at smohsin2@bloomberg.net

To contact the editors responsible for this story: Alex Wayne at awayne3@bloomberg.net, Joshua Gallu

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