WASHINGTON (CBSNewYork/AP) — President Donald Trump said Monday that he is “watching court cases and rulings” before taking action on raising age limits for purchasing some firearms.

Trump’s tweet came after his White House put out a plan to combat school shootings that doesn’t increase the minimum age for purchasing assault weapons to 21, an idea Trump publicly favored just last month, and leaves the question of arming teachers to states and local communities.

“On 18 to 21 Age Limits, watching court cases and rulings before acting,” the president said. “States are making this decision. Things are moving rapidly on this, but not much political support (to put it mildly).”

Instead, a new federal commission on school safety will examine the age issue as part of a package the White House announced Sunday in response to the school shooting in Parkland, Florida, last month that left 17 dead.

On Twitter, Trump described the school shooting effort as a “very strong improvement.”

“Legislation moving forward,” he said. “Bump Stocks will soon be out. Highly trained expert teachers will be allowed to conceal carry, subject to State Law. Armed guards OK, deterrent!”

In another tweet, he said “If schools are mandated to be gun free zones, violence and danger are given an open invitation to enter. Almost all school shootings are in gun free zones. Cowards will only go where there is no deterrent!”

The president quickly drew Democratic criticism over age limits. Sen. Richard Blumenthal, D-Conn., tweeted that Trump “couldn’t even summon the political courage to propose raising the age limit on firearm purchases – despite repeated promises to support such a step at a meeting with lawmakers.”

For now, the White House is backing a modest background check bill and a school safety measure, which both are expected to have widespread bipartisan support— even though some Republicans object and many Democrats say they are insufficient.

Republican Sen. Orrin Hatch of Utah, who wrote the school safety bill, tweeted he was “grateful” for the White House backing, calling the measure “the best first step we can take” to make students safer.

Education Secretary Betsy DeVos, who on Sunday called the proposal “meaningful actions, steps that can be taken right away to help protect students,” said Monday that the plan was “the first step in a more lengthy process.”

No deadline was set for the commission’s recommendations, but officials expected them within a year.

The administration also pledged to help states pay for firearms training for teachers and reiterated its call to improve the background check and mental health systems.

DeVos declined to say how many teachers should be armed.

“This is an issue that is best decided by local communities and by states,” DeVos said on NBC. “It’s not going to be appropriate in every location, but it is going to be appropriate in some places.”

The plan was immediately panned by gun control advocates, including the Brady Campaign to Prevent Gun Violence.

“Americans expecting real leadership to prevent gun violence will be disappointed and troubled by President Trump’s dangerous retreat from his promise,” said Avery Gardiner, the group’s co-president.

Trump was moved by the Florida school shooting and convened a series of listening sessions in the weeks after the massacre. In televised meetings with lawmakers, survivors of recent school shootings and the families of victims, Trump made a strong case for arming teachers and for increasing the age for purchasing long guns.

But Trump has also spoken repeatedly in recent weeks with the heads of the powerful National Rifle Association, which considers increasing the age of purchase to be an assault on the Second Amendment. The NRA on Friday sued Florida over a new gun law signed by Republican Gov. Rick Scott that bans the purchase of firearms by anyone under the age of 21.

During the meetings, Trump also advocated arming certain teachers and school staffers, arguing that gun-free schools are “like an invitation for these very sick people” to commit murder.

As part of the plan, the White House has directed the Justice Department to help states partner with local law enforcement to provide “rigorous firearms training to specifically qualified volunteer school personnel,” said Andrew Bremberg, director of the president’s Domestic Policy Council. The White House did not immediately say how much money would be made available.

Trump also called on states to pass court-issued Risk Protection Orders, which allow law enforcement to confiscate guns from individuals who pose risks to themselves and others, and temporarily prevent them from buying firearms.

And he called for the reform and expansion of mental health programs, as well as a full audit and review of the FBI tip line. The bureau has been criticized for not following up on warnings about the suspect in the Parkland school shooting.

(© Copyright 2018 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.)