Biden calls for comprehensive AR-15 ban amid calls for gun control

US President Joe Biden has called for a general ban on AR-15 rifles, the weapon used in Donald Trump shooting, during the NAACP's annual convention in Las Vegas.

"Join me in getting these weapons of war off the streets of America. An AR-15 was used in the shooting of Donald Trump... It's time to outlaw them," Biden said on Tuesday.

Biden said he was grateful that Trump was not seriously hurt at a campaign rally in Pennsylvania on Saturday.

The attempt on Trump's life on Saturday prompted the Biden campaign to pull its television ads, call off verbal attacks on the former President and focus instead on a message of unity.

"Our politics got too heated," said Biden.

However, Biden criticised Trump on a variety of fronts, including his handling of the economy during the coronavirus pandemic.

"Let me say it again because Trump is lying like hell about it - Black unemployment hit a record low under the Biden-Harris administration," Biden said.

"I am all in," said Biden, who was met with "four more years" chants as he spoke during the major gathering of Black voters.

The campaign's strategy previously was to focus on tough criticism of Trump as a threat to US democracy and to highlight his failure to admit his 2020 election loss and his felony convictions.

Now, it is trying to calibrate a less pugilistic message that still strikes a stark comparison between the two candidates.

Easing pressure

On Sunday, Biden used the formal setting of the White House Oval Office to ask Americans to lower the political temperature, recommit themselves to resolving their differences peacefully.

In an interview with NBC News, Biden said on Monday it was a mistake for him to use the term "bulls-eye" in reference to Trump during a recent donor campaign call.

The President postponed a trip to Texas on Monday, where he was expected to speak on the 60th anniversary of the Civil Rights Act at the Lyndon B. Johnson presidential library.

White House officials hope the Trump assassination attempt will ease pressure on Biden to step aside as his Democratic Party's candidate in response to concerns about his mental acuity and stamina to govern for another four-year term.

At the end of his remarks in Las Vegas, Biden addressed the criticism that he is too old for the job.

"Hopefully, today, I've demonstrated a little bit of wisdom. Here's what I do know. I know how to tell the truth. I know right from wrong. I know how to do this job. And I know the good Lord hasn't brought us this far to leave us now. We have more work to do," he said.

On Wednesday, Biden is scheduled to speak to Latino leaders at the UnidosUS Annual Conference, which is also in Las Vegas.

Meanwhile, Trump and Republicans are gathered in Milwaukee for the party's nominating convention that kicked off Monday with the selection of US Senator JD Vance as Trump's running mate.

Biden was also preparing to propose a major Supreme Court overhaul in the coming week that would include term limits for justices and an enforceable ethics code, the Washington Post reported on Tuesday, citing two sources familiar with the plans.