US President Donald Trump shows his signature on an Executive Order on Safe Policing for Safe Communities, in the Rose Garden of the White House in Washington DC on Tuesday. Photo: AFP

US President Donald Trump issued an order to improve policing Tuesday, calling for a ban on dangerous choke holds, but he stopped well short of demands made at nationwide protests against racism and police brutality.

"We have to break old patterns of failure," Trump said in a Rose Garden ceremony attended by police and Republican congressional allies, though no black civil rights representatives or political opponents.

The president has limited power over policing, which is run mostly at a state and local level. However, Trump said that he would use access to federal funding grants as leverage to persuade departments "to adopt the highest professional standards."

His executive order encourages de-escalation training, better recruitment, sharing of data on police who have bad records, and money to support police in complicated duties related to people with mental or drug issues.

A highlight of Trump's proposals, which he said could be complemented by legislation being negotiated in the Republican-controlled Senate, was ending choke holds "except if an officer's life is at risk," he said.

Trump called his initiative "a tremendous step" toward "safe, beautiful and elegant justice."

Critics, including the Democratic speaker of the House of Representatives, Nancy Pelosi, derided his efforts.

"The president's weak executive order falls sadly and seriously short of what is required to combat the epidemic of racial injustice and police brutality," she said in a statement. 

Trump began by announcing he'd just met in private with families of several black people killed in encounters with the police.

However, Trump's choice to keep the televised audience overwhelmingly white, male and focused on law enforcement representatives reinforced his main message.

Only a "very tiny" number of police commit wrongdoing, he said in remarks that frequently veered into a campaign speech about his accomplishments.

Democrats and civil rights groups say that full-scale rethinking of police culture, and even cuts in police funding are needed to bring necessary change to the US.

A first wave of unrest began more than three weeks ago, after the May 25 death of George Floyd, an African-American man, in Minneapolis.

Floyd stopped breathing when a white officer knelt on his neck, having already handcuffed him during arrest for a minor offense. Amateur video of the incident sparked demonstrations nationwide and in some places looting and arson.

New tension erupted last week after the death in Atlanta, Georgia, of Rayshard Brooks, another African-American whom police say was shot in the back as he ran away from arresting officers, having grabbed one of their tasers and aimed it at them.

AFP