President Trump slammed Democrats early Thursday morning for “doing nothing” about the Obama-era program that shielded hundreds of thousands of immigrants brought to the U.S. illegally as children from deportation, and noted the deadline is “rapidly approaching.”

The Trump administration rolled back the Deferred Action for Childhood Arrivals (DACA) program last September, but gave Congress a six-month window to craft legislation to protect the so-called Dreamers that were formerly covered by the program, by creating a path to legalization.

“March 5th is rapidly approaching and the Democrats are doing nothing about DACA,” Trump tweeted early Thursday. “They Resist, Blame, Complain and Obstruct—and do nothing. Start pushing Nancy Pelosi and the Dems to work out a DACA fix, NOW!”

The issue of DACA was one that caused the federal government to sustain a three-day government shutdown last month. Trump has worked with Republican lawmakers on a fix, but Congress and the White House have yet to come to a bipartisan agreement on a plan.

WHAT IS DACA AND WHY IS THE TRUMP ADMINISTRATION ENDING IT?

The program was created through executive order in 2012 by former President Barack Obama and allowed certain people who came to the U.S. illegally as minors to be protected from immediate deportation. The recipients of DACA were eligible to request “deferred action” for a period of two years, which was subject to renewal.

Individuals were able to request DACA status if they were under the age of 31 on June 15, 2012, came to the U.S. before turning 16 and lived in the country since June 15, 2007.

During Trump’s first official State of the Union address Tuesday night, he noted that “Americans are dreamers, too,” and discussed his “four pillars” of immigration reform, which included provisions for legal status for DACA recipients and others eligible for DACA status –the White House estimated that total to be 1.8 million people.

The president is speaking in West Virginia at the congressional Republican retreat Thursday, and is expected to discuss major policy items for his second year in office.

“Heading to beautiful West Virginia to be with great members of the Republican Party. Will be planning Infrastructure and discussing Immigration and DACA, not easy when we have no support from the Democrats,” Trump tweeted Thursday. “NOT ONE DEM VOTED FOR OUR TAX CUT BILL! Need more Republicans in ’18.”