As he prepares for his final year as governor of New Jersey, Philip D. Murphy on Tuesday proposed banning cellphones in schools and disclosed plans to blunt any additional limits on abortion access by the Trump administration.

Mr. Murphy also said he would work to address last year’s alarming 14 percent increase in roadway fatalities by overhauling the state’s 10 most dangerous intersections.

Mr. Murphy, a Democrat, began his seventh State of the State address in Trenton by acknowledging what he called “the elephant that is not in the room”: President-elect Donald J. Trump.

“I know there is some uncertainty and even concern about what this administration will bring,” the governor said, drawing the first round of applause from the standing-room-only crowd.

Mr. Murphy, who plans to attend Mr. Trump’s inauguration next week, said he “would never back away from partnering with the Trump administration” when doing so aligned with New Jersey’s priorities. But he vowed to fight Mr. Trump “if and when” those values are tested.

To that end, he said that New Jersey would stockpile a supply of mifepristone, one of two drugs used in medication abortions, in the event that Mr. Trump moved to limit its availability.

Aides to Mr. Murphy said New Jersey’s Department of Health had already begun gathering a six-month “strategic reserve” of medications, including mifepristone, which will be stored with abortion providers.

New Jersey law permits abortion throughout a pregnancy. But the governor also said that he would pursue legislation to end out-of-pocket costs for the procedure, reiterating a proposal he made last year.

As he outlined his priorities for his final year in office, Mr. Murphy said he would push for legislation to provide full pay to state workers on parental leave, make full-day kindergarten mandatory in the small number of towns that do not already offer it and permit 16- and 17-year-olds to vote in school board elections.

But perhaps the loudest and most sustained applause came when Mr. Murphy said he would direct school districts to adopt policies that ban cellphones in the state’s elementary, middle and high schools.

“Our children are inundated with screens,” Mr. Murphy said, adding that cellphone use had fueled a rise in cyberbullying and contributed to a mental health crisis among children.

“We will help establish phone-free schools,” he vowed.

New York’s governor, Kathy Hochul, said Monday that she planned to limit cellphone use in schools.

New York and New Jersey join a growing number of states, including Virginia, Ohio and Minnesota, that have moved to limit the use of the devices in schools. Los Angeles Unified became the largest school district in the United States to ban cellphones last year.

Mr. Murphy is prohibited by law from running for more than two consecutive terms, and November’s race to replace him is already in full swing.

Six prominent Democrats and four Republicans are competing for their party’s nomination to run for governor in the June primaries. The list of contenders includes the mayors of the state’s two largest cities, two members of Congress and a former Republican Assembly member who came within three percentage points of beating Mr. Murphy in 2021.

Indeed, the governor’s speech had a perfunctory air, and members of the audience at times appeared distracted; some repeatedly exited and re-entered the State Assembly chamber throughout the address.

The Republican leader of the State Senate, Anthony M. Bucco, called Mr. Murphy’s address a retread of costly, feel-good policy proposals.

“This state has become more and more and more unaffordable,” Mr. Bucco said.

“The days of spending outside of our means are coming to an end,” he added.

Still, the hourlong speech offered a window into major challenges facing New Jersey, including last year’s 14 percent increase in roadway fatalities.

Traffic fatalities nationwide have been declining. But last year in New Jersey, there were 691 traffic deaths, up from 606 the year before. Pedestrian fatalities soared by 32 percent.

The increase coincided with a drastic eight-month reduction in traffic enforcement by State Police troopers, who in July 2023 began writing far fewer tickets for speeding, drunken driving, cellphone use and other violations.

The reduced enforcement began a week after the state’s attorney general, Matthew J. Platkin, released a report critical of the performance of the State Police, New Jersey’s largest policing agency.

In August 2023, the first full month of the slowdown, troopers wrote 81 percent fewer tickets statewide, and crashes on the state’s two main highways immediately began to increase, according to records obtained by The New York Times through public records requests.

Mr. Platkin has appointed Preet Bharara, a prominent former federal prosecutor in Manhattan, to lead a criminal investigation of the slowdown.

Mr. Murphy is the only official in New Jersey with the power to replace the State Police superintendent, Col. Patrick Callahan, who led the department during the slowdown.

On Monday, when asked about the relationship between traffic fatalities and the reduced levels of enforcement, Mr. Murphy said, “If we’re not enforcing the laws on the books, that’s unacceptable.”

But he also worked to shift accountability for the slowdown away from himself and instead place full responsibility on Mr. Platkin and Colonel Callahan.

“It’s on their backs to get this into the right place,” Mr. Murphy said, adding that he had confidence in both men.

A spokesman for Colonel Callahan did not respond to a request for comment.

On Monday, Mr. Murphy signed a bill that created a commission dedicated to reducing the number of traffic fatalities in New Jersey to zero by 2040.

On Tuesday, he told lawmakers that he would “work with all of you to make New Jersey’s roads safer.”

He also announced plans to “overhaul” 10 of the state’s most dangerous intersections “to keep our families safe and to help prevent avoidable tragedies.”