Washington (CNN) President Donald Trump will seize the power of the bully pulpit this week amid the ongoing government shutdown, making his case for border wall funding in a prime-time Oval Office address that he will quickly follow up with a visit to the southern border.

The back-to-back events reflect a new attempt by the President to cast the deadlock over immigration as a national security crisis, a characterization that Democrats reject but which the President's aides believe will bolster support for a border wall.

The President tweeted he will "address the nation" Tuesday at 9 p.m. ET "on the Humanitarian and National Security crisis on our Southern border," two days before he is scheduled to visit the border. Trump indicated to aides over the weekend that he was interested in delivering a prime-time address to call attention to the issue, but it was not immediately clear whether TV networks had agreed to clear airtime for a presidential address.

I am pleased to inform you that I will Address the Nation on the Humanitarian and National Security crisis on our Southern Border. Tuesday night at 9:00 P.M. Eastern. — Donald J. Trump (@realDonaldTrump) January 7, 2019

Trump's Monday afternoon tweet about his plans to address the country come as the government shutdown begins its third week, with Trump and congressional Democrats at an impasse over Trump's demand for nearly $6 billion in federal funding to build a wall on the southern border.

A White House official said Trump wants to make his case about the government shutdown and wall funding in advance of Thursday's border trip.