Washington | Donald Trump has been slammed for a "horrific use of presidential power" after ordering police to disperse lawful protesters with tear gas and rubber bullets so he could stage photos of himself outside one of America's most venerated churches across from the White House in Washington.

In a dramatic split-screen made-for-television moment, Mr Trump also said he would trigger a 213-year old "insurrection" power to impose "law and order" across America and use the US military as the country slipped into its seventh-straight night of unrest following the slaying by police of African American George Floyd.