Story highlights Trump has said he'll make a decision about the Paris climate agreement soon

Washington (CNN) With President Donald Trump's expected decision to withdraw from the Paris climate agreement, the US could be about to join a very rarified club.

Nearly 200 countries agreed to the 2016 pact that would curb climate-changing climate emissions. The US would become only the third country to reject the accord -- joining a club that includes just two other members: Syria and Nicaragua.

Trump campaigned hard against the Paris agreement, and has called climate change a "hoax" perpetrated by the Chinese to gain economic advantage over the US.

After winning the election, he appointed as administrator of the Environmental Protection Agency Scott Pruitt, an Oklahoma lawyer who made a name for himself fighting the EPA's efforts on climate change and clean air, often working closely with the fossil fuel industry to do so.

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Nicaraguan and Syrian representatives in the US didn't respond to CNN's requests for comment about their decisions not to become party to the Paris agreement. If the US joins them in opposing the deal, it would make for an odd alignment -- and could be bad for US optics around the globe. Syria, of course, is waging a war against its own citizens that has raised concerns about possible crimes against humanity.

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