DONALD Trump might be forced to move his inauguration inside due to freezing weather, making the first indoor ceremony since 1985.

Bone-chilling temperatures are threatening Trump’s big day on January 20, according to insider reports.

Trump and Vice President-elect JD Vance are set to be sworn into office inside the US Capitol Rotunda due to the cold, according to CNN.

Washington DC is forecast to be at about 18 degrees when Trump is sworn in at noon on Monday, according to the National Weather Service.

The forecast high for the Capitol is in the upper teens to low 20s.

Wind chills could make the conditions even icier.

The ceremony will take place on what could be the coldest inauguration day since 1985 when Ronald Reagan was sworn in indoors.

Reagan gave a nod to the weather during his indoor ceremony 40 years ago.

“We stand again at the steps of this symbol of our democracy – well, we would have been standing at the steps if it hadn’t gotten so cold,” the late former president said with a laugh.

“Now we’re standing inside this symbol of our democracy.”

The temperature on Inauguration Day has only been below freezing once since Reagan’s inauguration – at Barack Obama’s first inauguration in 2009.