Trump says teachers with guns can only stop school shootings

President Donald Trump has reiterated the idea of arming teachers and sought offensive capabilities in schools to deter mass shootings.

This comes after last week's shooting at a high school that killed 17 people. The shooting sparked an intense push to restrict access to assault rifles fuelled by student activists who demanded concrete gun control measures.

"If, by the way, the bad guy thinks that somebody's in this room with a weapon that's going to be pointed at him, with live bullets, he's not going into the school. It's the one way you're going to solve it," Trump told reporters at a joint White House news conference.

"You're not going to solve it with gun-free spaces, because they'll get in there and they're going to be the only one with a gun. So, we need offensive capability, and we're going to be doing something about it," Trump said, responding to a critics to his proposal to arm selected school teachers with concealed arms.

Trump said it is 'very, very important' to have offensive capability, as well as defensive capability that's within the schools.

Insisting he will take action on guns and school shootings, Trump doubled down by saying that armed security guards are not enough and trained teachers should also carry guns.

"A security guard doesn't know the children, doesn't love the children," he said.

"The teachers love their children, they love their pupils, they love their students. They're doing it also for love.

"Now, they have to be very adept. I'm not talking about every teacher; I'm talking about a small percentage," he continued.

"Because, when you have a gun-free zone, you're really inviting people to come in and do whatever you have to do and, often times, get out," he said.

Trump said he spoke with the Republican Congressional leadership in this regard and they seemed to be energised on this issue.

"We take it very seriously. We want to put an end to it," he said.

The administration, he said is going to be very strong on background checks.

"I've spoken with many of our people in Congress, our senators, our congressmen and women. And there's a movement on to get something done. We want to be very powerful on background checks," he said.

"When we're dealing the mentally ill, as we were in this last case -- he was a very sick person and somebody that should have been nabbed.I guess they had 39 different occasions where they were able to see him or potentially see him. We want to be very powerful, very strong on background checks, and especially as it pertains to the mentally ill," said the US President.

IMAGE: US President Donald Trump bows his head during a prayer as he sits between Marjory Stoneman Douglas High School shooting survivors and students at the White House. Photograph: Jonathan Ernst/Reuters