US talk show host Jimmy Kimmel spoke passionately in the opening monologue of his show last night about America's gun problem, following the slaughter of at least 59 people at the hands of a gunman in his hometown of Las Vegas.

Struggling to hold back his emotions as he spoke through tears, he emphasised the need for change, directly challenging Donald Trump for easing gun control laws earlier this year as well as questioning why White House press secretary Sarah Sanders had claimed "now is not the time" to discuss gun control.

Kimmell also took on "Senate Majority leader Mitch McConnell, speaker of the house Paul Ryan, a number of other lawmakers who won't do anything about this because the NRA [National Rifle Association] has their balls in a money-clip".

On the "insufficient" messages of sending "thoughts and prayers" following what was the deadliest mass shooting in US history, Kimmel said: "They should be praying for God to forgive them for letting the gun lobby run this country."

He also showed the faces of 56 senators who, days after last year's shooting in Orlando where 49 people were killed, voted against the closing of loopholes that make it easier for people to buy guns without proper checks.

"What I'm talking about tonight isn't about gun control, it's about common sense," Kimmel said. "Common sense says no good will ever come from allowing a person to have weapons that can take down 527 Americans at a concert."

Host of The Late Show, Stephen Colbert, said "This afternoon the president called [the mass shooting] an act of pure evil. And I think he's right. So what then are we willing to do to combat pure evil?

"Doing nothing is cowardice. Doing something will take courage," he said, directly to Trump and other lawmakers.

"Now, President Trump, you said you want to be a transformative president, who doesn't care about the way things have always been done in Washington DC. This is your chance to prove it. And I mean this sincerely.

"You do not owe the Republicans anything. You know the Republicans tried to stop you from being president. Well, screw 'em! You want to 'Make America Great Again'? Do something the last two presidents couldn't do. Pass any kind of common sense gun control legislation that the vast majority of Americans want."

Late Night host Seth Meyers also joined the calls for change.

"It would so much more honest if you would just admit that your plan is to never talk about [gun control] and to never take any action," Meyers said in response to the "now is not the time" argument.