Officials under former President Obama called out the Trump administration Thursday for cutting the ObamaCare advertising budget by $5 million during one of its busiest times of year.

The Health and Human Services Department said in a statement that the government has pulled back about $5 million in ads as part of an effort to cut costs. The statement said HHS has already spent more than $60 million to promote sign-ups this year under former Obama's health care law.

Former Obama officials immediately accused the new administration of "sabotage."

Calling the decision "outrageous," former HealthCare.gov CEO Kevin Counihan said in a statement that the move could keep young, healthy people from getting into the insurance pool, thereby driving up costs.

"We know that more young people enroll during the final days of open enrollment, but they need to be reminded of the Jan. 31 deadline," Counihan said.

The advertising cutback was first reported by Politico.

A call to the HealthCare.gov national call center by The Associated Press found it to be up and running. An operator read a reporter a script saying that the transition to a new administration has not affected coverage for 2017, and people are still able to sign up.

The HHS website still linked featured a link for open enrollment and a blog promoting the law.

HealthCare.gov and its state counterparts offer subsidized private health insurance for people who don't have access to coverage on the job. This year the online insurance markets have been rocked by sharply higher premiums and dwindling choice of insurers, although nearly 9 in 10 customers receive final assistance.

Trump and leading Republicans have portrayed the markets as on the verge of collapse, and have cast their own effort to repeal and replace the Obama health overhaul as a rescue mission. Most independent experts say the situation is not as dire, although fixes are needed to strengthen the markets.

"President Trump is signaling he's the new sheriff," Rep. Chris Collins, R-N.Y., told Politico. "He's been elected with a mandate. He's not going to tolerate his employees contradicting and undermining his mandate to get this country going in another direction."

Some 11.5 million people had signed up nationwide through Dec. 24, or about 290,000 more than at the same time during the 2016 enrollment season. It's not clear, however, whether the Obama's administration's goal of 13.8 million enrolled for 2017 will be met.

More than 20 million people have gained coverage since the health care law passed in 2010, bringing the nation's uninsured rate to a historic low of around 9 percent. In addition to subsidized private insurance, the law offers states an option to expand Medicaid for low-income people.

Fox News' Edmund DeMarche and The Associated Press contributed to this report