President Trump — frustrated over Congress’ failure to repeal and replace ObamaCare — signed an executive order Thursday to make it easier for people to buy cheaper, bare-bones health insurance.

Team Trump said the order will allow small businesses and individuals to form associations to sponsor coverage that can be marketed across state lines.

“Since I became president of the United States, I just keep hearing repeal and replace, repeal, replace, well, we’re starting that process. And we’re starting it in a very positive manner,” Trump said at the White House, calling ObamaCare “a nightmare.”

The order, the president said, “directs the Department of Health and Human Services, the Treasury, and the Department of Labor, to take action to increase competition, increase choice, and increase access to lower-priced, high-quality health care options … and people will have great, great health care.”

Trump also said he would continue to pressure Congress to repeal and replace the Affordable Care Act.

Trump has long argued that interstate competition will lead to lower premiums — though experts say it could also hike premiums for older Americans and those with pre-existing conditions.

The new policies also do not have to provide the 10 “essential health benefits” covered under ObamaCare, including maternity care, emergency room visits, mental health treatment and others.

Trump’s move is likely to encounter opposition from medical associations, consumer groups and even insurers — the same coalition that has lobbied the GOP-controlled Congress against earlier repeal-and-replace efforts.

The president and GOP lawmakers had promised for years that their first order of business under a Trump administration would be to kill President Barack Obama’s signature legislative achievement.

But because of holdouts such as Sens. John McCain of Arizona, Susan Collins of Maine and others, various efforts to fulfill that campaign promise have crashed and burned, infuriating the president.

So Trump decided to take unilateral action, while offering few specifics beyond saying his move would let people cross state lines to obtain “great, competitive health care” costing the US government “nothing.”

It was unclear when the plans would become available, but it’s unlikely consumers could sign up during the 2018 open enrollment period, which begins Nov. 1.

Experts questioned Trump’s authority to issue such an order that would exempt some plans but not others from ObamaCare rules rather than pursuing the changes through legislation.

The action could open Trump to legal challenges from Democratic state attorneys general, who have said they will sue Trump if he tries to destroy ObamaCare.

With Post wires