Trump's Campaign Pledge to Revive Torture Rattled Britain's Spies, Report Shows

President Donald Trump's campaign pledge to bring back torture, including the controversial method of waterboarding, seriously concerned British spies before he entered the Oval Office, according to a new government report.

The document published by the Intelligence and Security Committee of Parliament (ISC), the body that oversees Britain's intelligence agencies—MI5, MI6 and GCHQ, on Tuesday reveals the fears inside the world's top security service about the future president's policy positions.

"Certain views that the president has expressed—particularly prior to his election—have the potential, if they were to become official policy, to pose difficulties for the U.K.-U.S.A. intelligence relationship," the document reads.

"These include, inter alia, the potential for a change in the U.S. relationship with Russia and Iran, and a change in policy on the use of torture and cruel, inhuman, or degrading treatment," it continues.

While his predecessor Barack Obama closed American black site facilities abroad, banned torture and attempted to close the Guantanamo Bay detention center, Trump promised to return the use of torture for the purposes of national security while on the presidential campaign trail in 2017.

"Don't tell me it doesn't work—torture works," he said. It was a pledge he reaffirmed after his January 20 inauguration.

Under the Bush administration, enhanced interrogation techniques were endorsed and used by the CIA against individuals linked to Al-Qaeda or suspected of extremist links who were detained after the 9/11 attacks. Much of the methods took place at Guantanamo Bay or at detention centers in Iraq where the U.S. military had invaded in 2003 to topple the regime of Saddam Hussein.

Evidence has emerged in the following years of members of the U.S. military and the CIA torturing prisoners in Iraq, particularly at the Abu Ghraib prison. Such methods included sleep deprivation, nudity, slapping prisoners in the face, food deprivation, waterboarding, and walling, where a detainee is slammed into a wall.

Trump, since his January 20 inauguration, has embarked on an elevated war against radical Islamists. He has doubled airstrikes in Yemen, Afghanistan and Somalia and banned residents of six Muslim-majority states from entering the U.S. for security reasons. He has also criticized European countries for what he regards as a light-touch approach to security and immigration in the wake of a series of attacks directed or inspired by the Islamic State militant group (ISIS).

But Britain's domestic security service MI5 was clear that it would not cooperate with the U.S. intelligence authorities in the use of torture if Trump was to alter the ban put in place by Obama.

"I have communicated internally already about this in MI5, that, you know, whatever happens, MI5 will operate within the law and by our values," the agency told the government body. "So if any of that changes on the U.S. side, there will be a consequence in the relationship but, you know, we will not collude in any sort of change in that sort of behavior. Of course we won't."

MI6, the British agency charged with conducting intelligence operations abroad, was similarly worried about the consequences of Trump reviving some of the darkest years of American behavior on foreign territory.

"If something happened which caused us fundamentally to revisit our presumption of legality [of the U.S. agencies' actions], which we have got now, hard won after many years after all the problems we have discussed [on detainee treatment and rendition], then that would be really difficult," MI6 told the government body.

The Trump administration angered British spooks when it claimed that GCHQ, the British government communications headquarters, had spied on the president when he was a candidate on behalf of Obama. GCHQ called the claim "utterly ridiculous," forcing an apology from White House officials.

The British intelligence establishment, in the wake of that episode and Trump's statements in and out of office, has put itself on alert for any significant and sudden changes to U.S. policy by the president, who has not held back on other inflammatory campaign promises, such as the relocation of the U.S. embassy to Jerusalem.

"The U.K. government must continue to keep a close eye on any changes in U.S. policy and take swift action if there are signs that these might run counter to British laws and values," the ISC concluded in its report.