WASHINGTON — The White House on Sunday vowed to help provide ‘‘rigorous firearms training’’ to some schoolteachers and formally endorsed a bill to tighten the federal background checks system, but backed off President Trump’s earlier call to raise the minimum age to purchase some guns to 21 years old from 18 years old.
Responding directly to last month’s gun massacre at a Florida high school, the administration rolled out a series of policy proposals that focus largely on mental health and school safety initiatives. The idea of arming some teachers has been controversial and has drawn sharp opposition from the National Education Association, the country’s largest teachers lobby, among other groups.
Many of the student survivors have urged Washington to toughen restrictions on gun purchases, but such measures are fiercely opposed by the National Rifle Association, and the Trump plan does not include any substantial changes to gun laws.
Rather, the president is establishing a Federal Commission on School Safety, to be chaired by Education Secretary Betsy DeVos, that will explore possible solutions, such as the age requirement for purchases, officials said.
DeVos characterized the administration’s efforts as ‘‘a pragmatic plan to dramatically increase school safety.’’
‘‘We are committed to working quickly because there’s no time to waste,’’ DeVos said on a Sunday evening conference call with reporters. Invoking past mass school shootings, she continued, ‘‘No student, no family, no teacher, and no school should have to live the horror of Parkland or Sandy Hook, or Columbine again.’’
The administration’s proposals come after 17 people were shot and killed last month at Marjory Stoneman Douglas High School in Parkland, Fla., a massacre that spurred officials in Washington to reevaluate gun laws.
Trump has said he was personally moved by the shooting — and by the persistent and impassioned calls for action from some of the teenage survivors as well as parents of the victims — and elevated the issue of school safety in his administration. He has called for raising the minimum age for purchasing an AR-15 or similar-style rifles from 18 to 21 years old.
‘‘Now, this is not a popular thing to say, in terms of the NRA. But I’m saying it anyway,’’ Trump said in a Feb. 28 meeting with lawmakers. ‘‘You can buy a handgun — you can’t buy one; you have to wait until you’re 21. But you can buy the kind of weapon used in the school shooting at 18. I think it’s something you have to think about.’’
But the White House plan released Sunday does not address the minimum age for gun purchases.
Pressed by reporters about the apparent backtracking, a senior administration said the age issue was ‘‘a state-based discussion right now’’ and would be explored by DeVos’s commission.
At a political rally Saturday night in Pennsylvania, Trump mocked the idea of commissions to solve the nation’s drug epidemic.
‘‘Do you think the drug dealers who kill thousands of people during their lifetime, do you think they care who’s on a blue-ribbon committee?’’ Trump said. ‘‘The only way to solve the drug problem is through toughness.’’
Administration officials demurred Sunday night when asked why Trump found commissions an inadequate response to the drug epidemic but an appropriate way to respond to gun massacres.
‘‘There are not going to be one-size-fits-all approaches and solutions, and I think that that is a very cogent argument for having a commission,’’ said a senior administration official, who would only answer questions from reporters on the condition of anonymity.
The centerpiece of the administration’s plan is Trump’s vow to ‘‘harden our schools against attack.’’ Since almost immediately after the Parkland shooting, the president has advocated arming some teachers as a solution to stopping future massacres.
‘‘A gun-free zone to a maniac — because they’re all cowards — a gun-free zone is, let’s go in and let’s attack, because bullets aren’t coming back at us,’’ Trump said during a Feb. 22 listening session at the White House with teachers, students, and parents.
The administration will start working with states to provide ‘‘rigorous firearms training’’ to teachers and other school personnel who volunteer to be armed, said Andrew Bremberg, director of the White House Domestic Policy Council.
The White House has not proposed offering states new funding for this training.
The plan’s release came a day before Massachusetts officials, including US Senator Edward J. Markey, Mayor Martin J. Walsh of Boston, and Boston Police Commissioner William Evans planned to meet at police headquarters to reveal a proposal for federal gun legislation.
The bill, sponsored by Markey, would encourage states to adopt gun licensing standards similar to those in Massachusetts, according to a statement from the mayor’s office.
A spokesman for Boston Public Schools said Sunday night he could not yet comment on the president’s newly released proposals. Instead, he referred to a statement issued last month by Superintendent Tommy Chang in which he said arming teachers “is utterly illogical and will only result in making our students and teachers less safe.”
The NRA supports the idea of allowing armed teachers in schools.
Bremberg said the administration is backing two pieces of legislation: A bipartisan bill by Senators John Cornyn, Republican of Texas, and Chris Murphy, Democrat of Connecticut, that is designed to improve the accuracy and effectiveness of the National Instant Criminal Background Check System; and the STOP School Violence Act, which would authorize state-based grants to implement violence prevention training for teachers and students.
The administration also is urging all states to pass risk protection orders, as Florida recently did, allowing law enforcement officers to remove firearms from individuals who are considered a threat to themselves or others and to prevent them from purchasing new guns, Bremberg said.
Lastly, the administration wants to better integrate mental health, primary care and family services programs, and the president has ordered a full audit and review of the FBI tip line, he said. The FBI has said it ignored a warning that 19-year-old Nikolas Cruz might attack a school just weeks before he allegedly carried out the rampage in Parkland.
‘‘The president is determined to get to the root of the various societal issues that lead to violence in our country,’’ Bremberg said. ‘‘No stone will be unturned.’’Globe correspondents Jeremy Fox and Dylan McGuinness contributed to this report.