(CNN) Almost two-thirds of Americans -- 63% -- believe that the US should not withdraw from the agreement made with Iran to prevent the country from developing nuclear weapons. Only 29% believe the US should withdraw, according to a new CNN poll conducted by SSRS.

President Donald Trump is expected to announce Tuesday whether he will remove the US from the deal, which lifted some sanctions in exchange for curbs on Iran's nuclear program. Trump has repeatedly criticized the agreement, which was made under former President Barack Obama, as a bad deal and has threatened to pull out the US even though Iran has been certified by a UN organization as complying with the terms of the pact.

The strongest proponents of withdrawing from the treaty are Republicans (51% say the US should withdraw), conservatives (47%) and those who approve of the job Trump is doing as President (46%).

Support for remaining in the agreement comes even as a strong majority of 62% say they believe Iran has violated the terms of the agreement. Nineteen percent said Iran has not violated the terms, with the same share saying they have no opinion.

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