U.S. President Donald Trump, next to ‪Vice President Mike Pence‬, delivers remarks at a meeting of the National Space Council at the White House in Washington, U.S. June 18, 2018. REUTERS/Jonathan Ernst

NEW YORK (Reuters) - The Trump administration on Tuesday issued a finalized rule that will enable millions of Americans to buy skimpy health insurance plans that do not comply with key Obamacare coverage requirements, marking its latest effort to chip away at the healthcare law.

The rule, which the U.S. Department of Labor will post Tuesday, allows small businesses and those who are self-employed to band together and buy lower-cost health insurance policies, similar to large employers.

But these insurance plans would not be subject to requirements under the Affordable Care Act (ACA), commonly called Obamacare, which included mandatory coverage for a set of 10 essential health benefits, such as maternity and newborn care, prescription drug costs and mental health treatment. They are expected to be far less expensive than Obamacare plans.

Health providers, insurers and medical groups have warned that the plans could drive up premiums and make insurance unaffordable for some people by siphoning off healthy consumers who want cheaper coverage, leaving behind a sicker patient pool with higher medical costs in Obamacare plans.

The finalized rule is the Trump administration’s most recent effort to provide consumers with alternatives to Obamacare, former Democratic President Barack Obama’s signature domestic policy achievement. Republicans, who control both chambers of Congress and the White House, repeatedly failed last year to repeal and replace the law, a top presidential campaign promise of President Donald Trump.

Democrats blasted the rule as the latest effort by Republicans to sabotage Americans’ healthcare.

“The Republicans agenda is to inflict higher costs on sick Americans just to hand tax breaks to big corporations and billionaires,” House Minority Leader Nancy Pelosi said in a statement.

Republicans repealed the ACA’s so-called individual mandate, the requirement that most Americans purchase health insurance or else pay a fine, in an overhaul of the U.S. tax code last year. Trump last year also ended billions of dollars of insurance subsidies under the law. Both were aimed at keeping ACA insurance plans more affordable for millions of Americans.

Republicans have praised the new rule as providing cheaper health insurance options to those who cannot afford Obamacare plans or who do not want them.