US President Barack Obama said in an interview yesterday that the massacre at a Connecticut elementary school that killed 20 young children was “the worst day of my presidency”.

Obama also expressed scepticism about a proposal by the gun lobby group The National Rifle Association to introduce armed guards in every US school and admitted there would be resistance to new proposals to control firearms.

“The question is whether we are actually shook up enough by what happened here that it does not just become another one of these routine episodes where it gets a lot of attention for a couple of weeks and then drifts away,” Obama said.

“It certainly won’t feel like that to me,” he said in an interview with NBC’s Meet the Press.

“This is something that was the worst day of my presidency. And it’s not something that I want to see repeated.”

Obama has promised to unveil broad-based proposals to rein in gun violence in the US in the new year, but has also said he believes there is a right in the US Constitution for individuals to bear arms.

On December 14, 20-year-old Adam Lanza killed his mother in their home in Newtown, Connecticut before embarking on a horrific shooting spree at a local school.

He blasted his way into Sandy Hook Elementary School and shot dead 20 six- and seven-year old children and six adults with a military-style assault rifle before taking his own life with a handgun as police closed in.