President Donald Trump plans to sign an executive order on Thursday that will allow small businesses and individuals to buy health insurance that skirts Obamacare regulations.

Trump's executive order would relax standards for association health plans, which allow small businesses to unite to negotiate health insurance plans. The order is also expected to extend the availability of short-term insurance policies, which provide limited benefits, from three months to nearly one year.

Some Democrats and state regulators warn that allowing business groups to unite their members and sell inexpensive large-group insurance would result in low-cost insurance options being available for only healthy people, as well as in greater costs for the sick.

"By siphoning off healthy individuals, these junk plans could cannibalize the insurance exchanges," Topher Spiro, a vice president of the Center for American Progress, a liberal research and advocacy group, told The New York Times. "For older, sicker people left behind in plans regulated under the Affordable Care Act, premiums could increase."

The executive order is the latest effort by Trump and other Republicans to dismantle the Affordable Care Act, also known as Obamacare. In recent months members of the GOP have introduced bills aimed at overhauling the health care system, but were unable to muster the votes necessary to pass them.

Trump's plan comes just three weeks before the start of the next ACA open-enrollment season for people who don't have access to health benefits through an employer. However, the Health and Human Services, Treasury, and Labor Departments would first need to finalize the rules in order for new insurance plans to be sold next year.