Trump is due to speak Wednesday to employees at the Department of Homeland Security — which handles immigration — and sign orders there on refugees and national security, according to The Washington Post and CNN.

“Big day planned on NATIONAL SECURITY tomorrow. Among many other things, we will build the wall!” Trump tweeted late Tuesday.

Trump launched his presidential campaign with a promise to build a wall along America’s long — and porous — southern border with Mexico, coupled with a tough immigration stance.

He also called for a “total and complete shutdown of Muslims entering the United States” until authorities can better screen those who come into the country.

What remains unclear is how the orders would be implemented by Homeland Security Secretary John Kelly, who told his confirmation hearing that the border wall might not “be built anytime soon.”

On Thursday, Trump is expected to sign executive orders on immigration and on so-called sanctuary cities, where local officials refuse to cooperate with federal immigration authorities on such things as handing over illegal immigrants for deportation.

The orders would restrict immigration and access to the United States for refugees and visa holders from Iraq, Iran, Libya, Somalia, Sudan, Syria and Yemen, according to the Post, which noted that citizens from many of these countries already face big obstacles in obtaining US visas.