The White House has said Donald Trump supports the “concept” of raising the age limit for purchasing assault weapons to 21 – appearing to water down the President’s recent backing for an increase that has been opposed by the National Rifle Association (NRA).

Mr Trump appeared to endorse a higher age limit when he met with students and parents from a Florida high school, where a 19-year old former student is alleged to have killed 17 people using an AR-15 assault-style weapon.

But the President has not spoken about the proposal in recent days.

On Sunday, he had lunch with leaders of the NRA, which argues that people aged 18 to 20 should not have their constitutional right to buy a guy infringed upon. The powerful gun-rights lobbying group heavily backed Mr Trump during his presidential campaign.

“Don’t worry about the NRA. They’re on our side,” Mr Trump told more than 35 state governors during a White House meeting.

Later, during a White House briefing, Press Secretary Sarah Huckabee Sanders attempted to dispel belief that the President was being influenced by only the NRA on gun policy.

Florida shooting – in pictures Show all 10 1 /10 Florida shooting – in pictures Florida shooting – in pictures Police arrest a suspect in connection with the shooting at the Marjory Stoneman Douglas High School in Parkland, Florida Reuters Florida shooting – in pictures Parents wait for news after reports of a shooting at Marjory Stoneman Douglas High School in Parkland, Florida AP Florida shooting – in pictures Anxious family members wait for news of students AP Photo/Wilfredo Lee Florida shooting – in pictures Students being evacuated from the school AP Florida shooting – in pictures Students being evacuated from the school Getty Florida shooting – in pictures People gather waiting for word from students AP Florida shooting – in pictures Parents waiting for news on their children AP Florida shooting – in pictures People gather at a hotel where students were taken after the shooting Getty Florida shooting – in pictures Florida Governor Rick Scott speaks to the media as he visits Marjory Stoneman Douglas High School following the shooting AFP/Getty Florida shooting – in pictures Dr. Igor Nichiporenko, Medical Director Trauma, left, and Dr. Evan Boyer, Medical Director, Emergency Services, speak about treating victims and the suspect at a press conference outside Broward Health North hospital AP

“It was a productive conversation, and I think everyone is in agreement that things need to be done and we have to have some changes take place to do what we can to protect America’s kids,” Ms Sanders told reporters on Monday. “And members of the NRA want to be part of that discussion.”

She continued: And, as we’ve said, the President is taking information from a number of stakeholders. And to try to pretend like he’s being influenced by any one group would be ridiculous, considering the number of individuals he’s met with that come from both the far left to the far right, and a lot of those in between.”

Ms Sanders also told reporters Mr Trump still supports the “concept” of a higher age limit. But he is open to discussion about how that might be implemented, she added.