President Donald Trump talks to the media on the South Lawn of the White House, December 8, 2018.

President Donald Trump late Friday applauded a federal judge's ruling in Texas that ruled former President Barack Obama's signature health-care law was unconstitutional, and called on Congress to replace the current mandate with a new bill.

U.S. District Court Judge Reed O'Connor of Texas issued the decision, declaring that key portions of the legislation were inconsistent with the Constitution. O'Connor's ruling argued that the health-care law can not stand on its own since Congress last December repealed the individual mandate, which imposed a tax penalty on consumers who went uninsured.

Trump, who has long opposed Obamacare — and failed to rally the GOP behind an effort in 2017 to repeal and replace it —cheered the Texas decision. In response to the ruling, the president urged Congress in a tweet to pass a new "strong" health-care law that provides "great health-care and protects pre-existing conditions."

As I predicted all along, Obamacare has been struck down as an UNCONSTITUTIONAL disaster! Now Congress must pass a STRONG law that provides GREAT healthcare and protects pre-existing conditions. Mitch and Nancy, get it done!

Although a repeal and replace effort failed in the Senate, Trump was able to dismantle key parts of the law, and several health policy researchers have blamed his actions for much of the drop in enrollment this year.

Sign-ups on the federal health insurance marketplace have been low this season, tumbling 11.7 percent from the same time last year, according to the latest figures from Centers for Medicare and Medicaid Services.

Democratic California Attorney General Xavier Becerra, who led a group states in intervening to defend Obamacare, called the decision "an assault on 133 million Americans with preexisting conditions, on the 20 million Americans who rely on the ACA's consumer protections for healthcare."