President Trump claimed Monday that he would have rushed into the Florida high school during the mass shooting earlier this month there that killed 17 people, and he called it “disgusting” that an officer assigned to the school didn’t enter the building while the attack was underway.

“I really believe I'd run in, even if I didn't have a weapon,” Trump said during a White House meeting with governors from across the country, adding that he thinks the governors assembled also would have rushed into Marjory Stoneman Douglas High School. “You never know until you’re tested,” he added.

The White House meeting focused in part on the school shooting and the wider issue of gun control. Trump has been highly critical of former Broward County sheriff's deputy Scot Peterson, who remained outside the school during the Feb. 14 massacre in Parkland, Fla. Peterson resigned last week.

An attorney for Peterson on Monday denied that his client had acted unprofessionally or cowardly during the shooting.

Joseph DiRuzzo said Peterson didn't go inside the school because it had sounded as if the shooting was happening outside the building.

At the Monday meeting, Trump suggested he would act to regulate “bump stocks” even if Congress does not. The devices can be added to semiautomatic weapons to make them fire like fully automatic guns; they were used by the gunman who killed 58 people last year in Las Vegas. The device was not used in the Parkland, where the gunman wielded a legally purchased AR-15 semiautomatic weapon.

Trump said he would “write off” bump stocks, suggesting he would take action to ban the devices. “I don’t care if Congress doesn’t” act, he said. “We’re getting rid of it. You put it into the machine-gun category, which is what it is.”

Trump told the governors Monday that he had lunch over the weekend with leaders of the National Rifle Association, and he predicted that the powerful gun lobby will “do something” to respond to the escalating concern nationwide about guns.

“Don’t worry about the NRA. They’re on our side,” Trump said.

In a sign the Senate could move quickly on one modest gun measure, Republican leaders privately polled GOP senators Monday about the Fix NICS Act, an NRA-backed bill that would create additional incentives and penalties to ensure agencies report pertinent data on potential guy buyers to the National Instant Criminal Background Check system.

If all 100 senators agree to pass the bill, or at least limit debate on it, the legislation could quickly pass the chamber. But any one senator can hold up the bill, forcing it through time-consuming procedural hurdles. It is also unclear whether the House would pass the bill as a stand-alone measure. Lawmakers in that chamber passed the Fix NICS Act in December, but attached it to a bill that would require states to recognize concealed-carry permits from other states — a measure favored by the NRA but strongly opposed by gun control advocates.

At least one House GOP leader said the Fix NICS bill would be unlikely to get a stand-alone vote. “I would not want to bring a bill up that only addresses one issue with gun safety, because frankly concealed carry reciprocity will increase gun safety,” House Majority Whip Steve Scalise (R-La.) said in a Friday interview, suggesting the chambers would instead form a conference committee to come up with a compromise bill.

Also at the meeting with governors, Trump said he wanted to make it easier for law enforcement to take guns away from mentally ill people, saying police should have “immediate access” to their weapons.

“When we see somebody's sick like this guy, when the police went to see him, they didn't do a good job,” he said. “But they have restrictions on what they can do. We've got to give them immediate access to taking those guns away, so that they don't just leave, and he's sitting there with seven different weapons. Got to give them immediate access.”

Last year, Trump signed into law a repeal of Obama-era regulations that made purchasing a gun more difficult for people who receive Social Security payments for mental illnesses.

Trump also called for a revitalization of mental institutions.

“We’re going to have to start talking about mental institutions,” he said. “In the old days,” the president added, it was easier to commit people to mental institutions if they acted “like a boiler ready to explode.”

Trump urged governors to revisit the closure of mental institutions, saying there should be a half-measure between institutionalization and leaving potentially dangerous people “in their house.”

Nevada Gov. Brian Sandoval (R) and Montana Gov. Steve Bullock (D), the chair and vice chair of the National Governors Association, met with reporters after the meeting at the White House and said they were more confident than in the past that this mass shooting would lead to action on school safety, guns and mental health issues.

“The status quo is not acceptable. We’ve got to do some things,” Sandoval said. He added, “The president said this is number one on his agenda now, absolutely number one. I think it’s going to be the same for governors.”

Bullock said the president’s proposal to arm teachers drew opposition from a number of governors. “I have three kids,” he said. “I don’t want my teachers armed and I don’t think most Americans do.”

During the White House meeting, Washington Gov. Jay Inslee (D), who chairs the Democratic Governors Association, bluntly told the president to shelve the idea. Saying that educators should educate, he added, “I just suggest we need a little less tweeting and a little more listening and let’s just take that off the table and move forward.”

Dan Balz and Mike DeBonis contributed to this story.