Washington (CNN) President Donald Trump on Wednesday promised a further ratcheting up of economic sanctions against Iran in the wake of attacks on two Iraqi military bases housing American troops.

"The United States will impose additional punishing economic sanctions on the Iranian regime," Trump said in a brief White House address . The President said the additional sanctions on Iran would stay in place until the Islamic Republic "changes its behavior" toward the United States and countries in the region.

But it was not immediately clear what shape those sanctions would take. The Treasury Department did not immediately respond to requests for comment.

The military strike, which the President said caused no casualties, came days after the targeted killing of Gen. Qasem Soleimani , the head of Iran's elite Quds Force, by the US.

The Trump administration has been ramping up economic penalties as part of its "maximum pressure" campaign on Tehran since the United States exited the Iran nuclear deal in May 2018.

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