WASHINGTON — Over a thousand former Justice Department officials have signed a statement calling on Donald Trump's attorney general to resign over his interference in the sentencing of the president's friend and ally Roger Stone.

The statement, circulating online on Sunday, accused Trump and Attorney General William Barr of "openly and repeatedly" flouting the bedrock principle of evenhanded, non-partisan application of the law.

"A person should not be given special treatment in a criminal prosecution because they are a close political ally of the president," the statement said.

"Governments that use the enormous power of law enforcement to punish their enemies and reward their allies are not constitutional republics; they are autocracies," it said.

Prosecutors last week recommended that Stone be sentenced to seven to nine years in prison after he was convicted of obstructing a congressional investigation into Russian election meddling and lying to investigators.

Trump blasted the recommendation on Twitter as "horrible and very unfair." Barr intervened hours later, withdrawing the recommendation as "extreme and excessive and disproportionate."

Facing a mounting outcry, Barr rebuked Trump in a television interview on Thursday, saying the president's tweets were making his job "impossible."

In their statement, the former Justice Department officials welcomed Barr's "belated acknowledgement" of the damage done by Trump's tweets.

"But Mr. Barr's actions in doing the president's personal bidding unfortunately speak louder than his words," it said.

"Those actions, and the damage they have done to the Department of Justice's reputation for integrity and the rule of law, require Mr. Barr to resign."

White House advisor Kellyanne Conway defended Trump's actions on the "Fox News Sunday" program, insisting the president had issued no orders to Barr while contending it was "disingenuous" to say presidents don't comment on criminal matters.

The former officials, however, said it was unheard of for the department's senior leadership to overrule line prosecutors "in order to give preferential treatment to a close associate of the president, as Attorney General Barr did in the Stone case."

"It is even more outrageous for the attorney general to intervene as he did here — after the president publicly condemned the sentencing recommendation that line prosecutors had already filed in court." — AFP