Maryland Gov. Larry Hogan announced Thursday that he will withhold $68 million in funding for high-cost school systems this year, thwarting the wishes of Democratic legislators and top officials in Montgomery and Prince George’s counties.

The General Assembly passed a measure in April requiring the state to fully fund a program that sends extra money to the state’s costliest school systems.

While Hogan (R) said at a news conference Thursday that he will not veto the funding measure, he also signaled his distaste for the bill by announcing that the full spending would not flow until next fiscal year.

“This is more mandated spending, which is a bad idea,” he said.

With the governor’s decision not to release the $68 million this year, at least part of the withheld money will go toward funding public-employee pensions, which the administration has named as one of its top priorities.

The decision is a particular setback for Prince George’s and Montgomery counties, which would have received $20 million and $17 million in extra money, respectively. Those counties — both of which voted overwhelmingly for Hogan’s Democratic opponent in the November election — are also waiting anxiously to hear whether the new governor will cancel plans for the light-rail Purple Line, which would connect New Carrollton and Bethesda.

Teachers, lawmakers and local leaders quickly criticized Hogan’s action.

“His continued insistence on shortchanging $68 million from our schools is going to have a direct impact on student learning in the coming school year, and that’s in­cred­ibly disappointing,” said Sean Johnson, a lobbyist for the Maryland State Education Association.

Senate President Thomas V. Mike Miller Jr. (D-Calvert) called Hogan’s decision a “declaration of war on the children of the state of Maryland.”

Miller noted that Maryland’s schools have repeatedly ranked among the best in the country in recent years, adding, “I wonder where we’ll fall next year.”

House Speaker Michael E. Busch (D-Anne Arundel) said Hogan’s decision will “put his relationship in a very tenuous situation with [jurisdictions] like Montgomery, Prince George’s and Baltimore.”

Montgomery County Executive Isiah Leggett (D) expressed disappointment with the governor’s announcement. “This is a tremendous need for the county and for the state,” he said.

Hogan agreed earlier this year to provide half of the $136 million needed to fully fund a supplement to the state’s costliest school systems under a formula known as the Geographic Cost of Education Index. The legislature responded with a bill requiring the state to fund the full amount beginning in the next fiscal year, and the governor decided Thursday not to veto the measure.

Since the end of the legislative session, the governor has faced incessant lobbying from teachers unions, Rep. Chris Van Hollen (D-Md.) and many others to release the funds.

Hogan noted Thursday that he has increased education spending to a record high and that he is the only governor to approve the index-based funding — which he described as “bonus money” — during his first year in office.

“It takes more than just money to solve the problems we have in education,” Hogan said. “My administration is committed to improving and to fully funding education at every level, and we are going to put our money where our mouth is.”

Johnson, the union official, said that per-student spending has declined despite the rise in total education funding and that the recommended amounts for high-cost school systems have been fully funded for six consecutive years.

“We don’t go backwards on our kids,” he said. “Unfortunately, in the first term of Governor Hogan, we have.”

Johnson also criticized Hogan’s use of the term “bonus money” to describe the funds.

“It’s not bonus money,” he said. “This is about personnel. This will have a definite impact on the number of teachers we have in the system.”

Hogan aides countered that the statewide average on per-student spending has increased. And Hogan has repeatedly suggested that the school systems need more accountability rather than extra funds.

“What we will not do is rob the pensions of Maryland citizens at the demand of special-interest groups and politicians who repeatedly choose to throw more and more of our hard-earned tax dollars at problems instead of actually focusing on finding real solutions,” he said Thursday.

Hogan also criticized the city of Baltimore for reducing its spending on education over the past two years. “It’s our top priority,” he said. “It’s apparently not theirs.”

Baltimore will miss out on $11 million this year because of the governor’s decision.

Johnson said local governments “definitely have a responsibility to keep up with their funding,” but he said the General Assembly has passed legislation in recent years requiring districts to maintain per-student spending levels.

“This is disappointing that the state is going to do less while local governments are, in fact, maintaining if not in most cases doing more,” he said.

Bill Turque and Robert McCartney contributed to this report.