President Donald Trump has declared that he believes torture works as his administration prepared a sweeping review of how America conducts the war on terror.

It includes possible resumption of banned interrogation methods and reopening CIA-run "black site" prisons outside the United States.

In an interview with ABC News, Mr Trump said he would wage war against Islamic State militants with the singular goal of keeping the US safe.

Asked specifically about the simulated drowning technique known as waterboarding, Mr Trump cited the extremist group's atrocities against Christians and others and said: "We have to fight fire with fire."

Mr Trump said he would consult with new Defence Secretary James Mattis and CIA director Mike Pompeo before authorising any new policy.

However, he said he had asked top intelligence officials in the past day: "Does torture work?"

"And the answer was yes, absolutely," Mr Trump said.

He added that he wants to do "everything within the bounds of what you're allowed to do legally".

Everything within the bounds of what you're allowed to do legally

A clip of Mr Trump's interview was released after The Associated Press and other news outlets obtained copies of a draft executive order being circulated within his administration.

Beyond reviewing interrogation techniques and facilities, the draft order would instruct the Pentagon to send newly captured "enemy combatants" to Guantanamo Bay, Cuba, instead of closing the detention facility as former president Barack Obama had wanted.

Altogether, the possible changes could mark a dramatic return to how the Bush administration waged its campaign against al Qaida and other extremist groups.

Trump spokesman Sean Spicer, questioned about the draft order, said it was "not a White House document" but would not comment further.

The draft says US laws should be obeyed at all times and explicitly rejects "torture".

However, its reconsideration of the harsh techniques banned by Mr Obama and Congress raises questions about the definition of the word and is sure to inflame passions in the US and abroad.

After the September 11 attacks, President George W Bush authorised a covert programme that led to dozens of detainees being held in secret locations overseas and to interrogation tactics that included sleep deprivation, slapping and slamming against walls, confinement in small boxes, prolonged isolation and even death threats.

Three detainees faced waterboarding, and many developed psychological problems.

While some former government leaders insist the programme was effective in obtaining critical intelligence, many others say the abuses weakened America's moral standing in the world, hurt morale among intelligence officers and proved ineffective before Mr Obama shut it down.

The AP obtained the draft order from a US official, who said it had been distributed by the White House for consultations before Mr Trump signs it.

The Pentagon did not immediately comment and Mr Spicer, Mr Trump's press secretary, said: "I have no idea where it came from."

However, reports of the upcoming order quickly sparked alarm among Republicans and Democrats.

"The president can sign whatever executive orders he likes. But the law is the law," said Republican Senator John McCain, tortured himself as a prisoner during the Vietnam War.

"We are not bringing back torture in the United States of America."

On the campaign trail, Mr Trump spoke emphatically about toughening the US approach to fighting IS.

He said he would authorise waterboarding and a "hell of a lot worse".

After winning the election, however, he appeared to backtrack, pointedly citing Mr Mattis' advice that torture is ineffective.

Mr Pompeo said in his confirmation hearing that he would abide by all laws.

However, he also said he would consult with CIA and other government experts on whether current restrictions were an "impediment to gathering vital intelligence to protect the country or whether any rewrite of the Army Field Manual is needed".

Specifically, Mr Trump's draft order calls for reinstating an executive order - "to the extent permitted" by current law - that President Bush signed in 2007 and Mr Obama later revoked.

Mr Trump's draft would reverse two other executive orders.