President Donald Trump will make a “major announcement” Saturday about border security on what by then will be the 29th day of the partial government shutdown.

Three minutes after the White House call a “lid” Friday night and reporters headed for the gate, the president fired off a tweet, saying his remarks will focus on “the Humanitarian Crisis on our Southern Border, and the Shutdown, tomorrow afternoon at 3 P.M., live from the @WhiteHouse.”

I will be making a major announcement concerning the Humanitarian Crisis on our Southern Border, and the Shutdown, tomorrow afternoon at 3 P.M., live from the @WhiteHouse.

— Donald J. Trump (@realDonaldTrump) January 18, 2019

The president nixed Speaker Nancy Pelosi and other Democrats’ planned Afghanistan trip to meet with U.S. troops and NATO officials, saying he wanted her to stay in Washington for talks to end the shutdown.

But he did not formally invite her to the White House for any Friday or weekend talks. Aides such as Kellyanne Conway said the speaker has an “open” invitation.

Trump’s promised announcement comes after a few days of a tit-for-tat with Pelosi, including her requesting he delay his State of the Union address and him nixing the trip. Her office accused him of leaking her try at flying commercial and salvaging the trip. But Trump’s top spokeswoman, Sarah Huckabee Sanders, on Friday said she “absolutely” thinks Pelosi’s office was lying when it issued a statement accusing the White House of leaking the Democrats’ commercial travel plans to the war-torn country.

Watch: ‘I’m not sure what’s going on, but I object’: Confusion on House floor Thursday during attempted shutdown-ending vote