In a bid to expand access to affordable healthcare coverage, the Trump administration early Thursday rolled out proposed rules that would allow more small businesses and self-employed workers to band together to buy insurance.

The rule is part of the administration’s objective to encourage competition in the health insurance markets and lower the cost of coverage. But some experts say expanding access to these “association health plans,” which aren’t subject to many of the same regulations and consumer protections as other health plans sold under the Affordable Care Act, could weaken the individual health insurance market.