WASHINGTON (AFP) - Obama plans to bar US police from getting tracked armored vehicles, bayonets, grenade launchers, and large-caliber firearms, in response to accusations that law enforcement has become too militarised.

After controversy over the policing of high-profile protests in Baltimore, Maryland and Ferguson, Missouri, the White House said Monday that Obama will move to choke police access to military equipment.

"At times, the law enforcement response to those protests was characterised as a 'military-style' operation," said a 50-page report that will form the basis of Obama's announcement later Monday. Those disturbances showed "law enforcement officers atop armored vehicles, wearing uniforms often associated with the military, and holding military-type weapons."

The protests were prompted by the killing of unarmed black men by police. According to US law, the use of deadly force by police is only justifiable if a suspect poses a credible threat to the officer or the public.

The White House said it hopes to strengthen "all-important trust between the law enforcement officers who put their lives on the line every day, and the communities they have sworn to serve and protect."

The recommendations include barring the use of some military uniforms, firearms of greater than .50 caliber, grenade launchers and bayonets.

Police will still be allowed under certain circumstances to use wheeled armored vehicles, Humvees, drones and riot batons. Many of the recommendations have long been advocated by civil liberties groups, which say billions of dollars' worth of military equipment is transferred from the federal government to police departments every year.