President Donald Trump on Thursday used his presidential powers to undermine Obamacare after fellow Republicans in Congress failed to repeal the 2010 law.

According to Reuters, it was Trump’s most concrete step to undo Obamacare since he took office in January promising to dismantle former President Barack Obama’s signature domestic policy achievement.

Trump signed an executive order aimed at letting small businesses band together across state lines to buy cheaper, less regulated health plans for their employees with fewer benefits.

The House of Representatives in May passed Republican legislation to gut Obamacare. But attempts by Senate Republicans to repeal and replace Obamacare failed in July and September, in part because the proposed legislation would have caused millions of Americans to lose healthcare coverage.

Republicans call Obamacare a government intrusion into Americans’ healthcare, and have been promising for seven years to scrap it.

Trump’s order weakens Obamacare in part by giving people more access to plans that do not cover essential health benefits such as maternity and newborn care, prescription drugs, and mental health and addiction treatment.

Obamacare, known formally as the Affordable Care Act, requires most small business and individual health plans to cover those benefits.