Washington (CNN) Treasury Secretary Steven Mnuchin said Thursday that the financial messaging service that moves money around the global banking system will be cutting off Iran's Central Bank.

"I understand that SWIFT will be discontinuing service to the Central Bank of Iran and designated Iranian financial institutions," Mnuchin said in a tweet. "SWIFT is making the right decision to protect the integrity of the international financial system."

The decision by SWIFT means Iran's Central Bank will be cut off from the international banking system and will cause significant economic pain, observers say. The move comes as the US tries to squeeze Iran with a slew of sanctions and economic measures that administration officials say are meant to make the regime change its behavior.

On Wednesday, Secretary of State Mike Pompeo told BBC Persian that Iran's "leadership has to make a decision that they want their people to eat. They have to make a decision that they want to use their wealth to import medicine, and not use their wealth to fund" destabilizing activities in the region."

The Trump administration on Monday reimposed all sanctions against Iran that had been lifted as part of the 2015 nuclear agreement. Treasury officials said at the time that the US had advised Swift to stop providing services to certain Iranian entities. And they made clear they were willing to force the matter.

I understand that SWIFT will be discontinuing service to the Central Bank of Iran and designated Iranian financial institutions. SWIFT is making the right decision to protect the integrity of the international financial system. — Steven Mnuchin (@stevenmnuchin1) November 8, 2018

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