Restrictions on the sale of surplus military equipment to American police forces are being lifted by the Trump administration.

The move, which will see forces supplied with grenade launchers and an arsenal of other high powered weapons, is certain to reignite fears that US police departments are being turned into paramilitary forces.

Jeff Sessions Attorney General announced the program at a national convention of the Fraternal Order of Police on Monday.

Restrictions were put in place by the Obama administration in 2015 following a number of high profile killings of black men by the police, including Michael Brown, an unarmed teenager in Ferguson, Missouri.

Misgivings about the use of weapons better-suited to the battlefield were not only voiced by Democrats.