United States President Donald Trump on Thursday signed an order that makes it easier for citizens to buy basic health insurance plans that have fewer benefits for consumers.

Trump issued the executive order with sweeping changes to the US’ Affordable Care Act – or Obamacare – the most concrete step yet to dismantle former President Barack Obama’s signature domestic policy, Reuters reported. Trump’s order comes after fellow Republicans in Congress failed to repeal the 2010 law.

The new order may not be enforced until 2019 as it could be obstructed by Democratic state attorneys general, Reuters reported.

The key difference lies in how small businesses can buy healthcare plans. Trump’s order will allow them to band together to buy cheaper, but less regulated health plans for their employees. These, however, will have fewer benefits.

While the White House said Trump’s order aims to give people more access to cheaper plans, these plans will not cover essential health benefits such as maternity and newborn care, prescription drugs, and mental health and addiction treatment. Obamacare, on the other hand, required most small business and individual health plans to cover these benefits.

“The cost of the Obamacare has been so outrageous, it is absolutely destroying everything in its wake,” Trump said at a White House signing ceremony.

Senate Democratic leader Chuck Schumer accused Trump of “using a wrecking ball to single-handedly rip apart our healthcare system”. Senator Richard J Durbin, a Democrat of Illinois, wrote on Twitter, “The President is destroying health care to make a political point.”

Experts also questioned if Trump had the legal authority to expand association health plans.