WASHINGTON – Another GOP senator will reject President Trump’s national emergency declaration that would allow him to build a wall on the southern border, setting up a scenario for Trump to issue his first veto.

“I can’t vote to give the president the power to spend money that hasn’t been appropriated by Congress,” Sen. Rand Paul (R-Ky.) said at a GOP event in Kentucky Saturday, according to the Bowling Green Daily News.

“We may want more money for border security, but Congress didn’t authorize it. If we take away those checks and balances, it’s a dangerous thing,” he said.

Paul joins at least three other Senate Republicans – Sens. Thom Tills of North Carolina, Susan Collins of Maine and Lisa Murkowski of Alaska – who said they won’t support Trump using emergency powers to take billions from Department of Defense construction programs to build a wall on the Mexican border.

Congress refused to appropriate $5.6 billion in funds Trump wanted in a spending bill to end a 35-day government shutdown in January.

Trump’s emergency declaration is an abuse of executive authority used to bypass the will of Congress, the senators believe.

If the four senators join with all the 47 senators who caucus with the Democrats, there would be a bipartisan majority to block Trump’s emergency declaration.

The measure already passed the Democrat-controlled House.

Trump has pledged to veto any effort by Congress to stop construction of the wall.

But Congress does not appear to have the 2/3 majority needed to override his veto – meaning Trump’s declaration could stay in place.

The emergency declaration is under court challenge by states like New York.

A rep for Paul did not immediately respond to the Post for further comment.