The White House unveiled proposals Sunday intended to improve school safety and mental health.

But officials backed off President Donald Trump's call to raise the age limit on buying certain firearms.

The proposals came weeks after 17 people were killed in a school shooting in Parkland, Florida.

The White House has backed off President Donald Trump's call to raise the federal age limit to buy certain firearms, instead proposing efforts designed to improve the mental-health system and background checks on gun purchases and to beef up security in schools.

The administration's plans include working with states to provide "rigorous" gun training for "specially qualified" teachers and staff members, officials said. Teacher groups such as the National Education Association have condemned proposals to arm teachers.

"We are committed to working quickly because there's no time to waste," Secretary of Education Betsy DeVos said in a conference call with reporters. "No student, no family, no teacher, and no school should have to live the horror of Parkland or Sandy Hook or Columbine again."

The White House has faced pressure to act in the aftermath of the shooting at Marjory Stoneman Douglas High School in Parkland, Florida, last month that left 17 people dead. Gun-control advocates, including some of the teenage survivors of the Parkland massacre, have pressured officials to make it more difficult for people to acquire assault-style rifles like the kind used in the shooting.

Shortly after the shooting, Trump suggested raising the federal age limit for purchasing such weapons to 21 from 18 — a stance opposed by the National Rifle Association. Gov. Rick Scott of Florida signed a bill this week raising the limit to 21 on all firearm purchases in his state, prompting a lawsuit from the NRA.

On Sunday, the White House referred to Trump's age-limit proposal as "a state-based discussion right now" and said the idea would be explored by a committee headed by DeVos.

"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," a White House official said during the conference call.

"The president is determined to get to the root of the various societal issues that lead to violence in our country," said Andrew Bremberg, the director of the White House's Domestic Policy Council. "No stone will be unturned."