President Donald Trump’s first White House Oval Office address, which will focus on border security, is set for tonight at 9 PM ET/6 PM PT. The White House has asked for eight minutes of primetime air for the speech, which will result in delays and rescheduling of regular programming on the Big 4, which all have agreed to telecast Trump live.

Deadline will livestream the speechg here.

The cable news networks annd PBS also will go live on air and their online platforms, as will C-SPAN. The White House YouTube channel also will have the speech, which is expected to be followed by a formal response by the Democrats. The broadcast nets expect normal programming to resume at 9:30 PM ET/6:30 PM PT.

The Trump administration has been sending heavier smoke signals the past few days about its desire to fund a wall on the U.S. southern border — the main sticking point that resulted in the partial shutdown of the U.S. government, which is in its 18th day. It is expected to be Trump’s main topic tonight.

On Tuesday morning, Trump sent a letter to Congress calling on lawmakers to pass legislation “that will address the security and humanitarian crises on our Southern Border.” Among the requested funding is $5.7 billion for construction of “a steel barrier” on the U.S.-Mexico border spanning 234 miles.

Trump reportedly is considering declaring the border situation a national emergency, though that likely won’t be part of his speech tonight. The declaration could trigger immediate funding for a border wall, as well as likely lawsuits challenging the move.