With Congress' repeated failures to overturn the Affordable Care Act, President Donald Trump on Thursday morning signed an executive order that opens the door to dismantling Obamacare.

The new order directs federal agencies to develop new policies to increase competition and lower costs. It aims to lower premiums for healthy people, and it may spur a process to allow small businesses to buy lower-priced healthcare insurance plans that offer fewer benefits than the 2010 law requires.

"The competition will be staggering," Trump said in a news conference at the White House. "Insurance companies will be fighting to get every single person signed up, and you will be hopefully negotiating, negotiating, negotiating, and you'll get such low prices for such great care."

Trump said his order will cost the federal government "virtually nothing," for "great, great healthcare," and he criticized Democrats and some Republicans for stalling his promise to repeal and replace the ACA.

The president's order "is a step in the right direction," said Robert E. Moffit, a senior fellow in The Heritage Foundation's Center for Health Policy Studies in Washington, D.C. The foundation, with over 500,000 members, calls itself "the most influential conservative group in America."

"The order allows small businesses and their employees to form larger associations and to buy affordable healthcare plans in individual and group markets, marked by high premiums and deductibles now," Moffit said.

An official with a top trade group for healthcare insurers weighed in on the president's order minutes after he signed it.

"Health plans remain committed to certain principles," said Kristine Grow, senior vice president of communications for America's Health Insurance Plans, in a statement. "We believe that all Americans should have access to affordable coverage and care, including those with pre-existing conditions.

"We believe that reforms must stabilize the individual market for lower costs, higher consumer satisfaction, and better health outcomes for everyone. And we believe that we cannot jeopardize the stability of other markets that provide coverage for hundreds of millions of Americans."

Anthony Wright, head of Health Access California, a consumer advocacy coalition, warned that the president's order threatens to destabilize insurance markets, undo benefit standards and eliminate protections, possibly propelling insurers to depart the ACA's individual small group markets.

"The executive order directs federal agencies to create large loopholes in the ACA's patient protections, particularly for those with pre-existing conditions, who will likely see increased premiums and limited choices as a result," Wright said in a statement. "This executive order is a lose-lose proposition, both for healthy people who are lured into a substandard plan that may not actually cover the care they eventually need, and for the rest of us who are left in a smaller and sicker insurance pool facing higher premiums and fewer choices."

Meanwhile, the president is instructing Secretary of Labor Alexander Acosta and Secretary of Treasury Steven T. Mnuchin to explore how they can allow more businesses to offer tax-free health reimbursement arrangements to compensate their employees for their healthcare expenses. Currently, around a third of small business employees receive healthcare at work, forcing millions of these workers to enroll in ACA insurance exchanges or remain uninsured and pay the individual mandate penalties, according to the president.

Trump's executive order is sure to spur legal challenges.