Donald Trump has called the US leaks of evidence relating to the Manchester attack investigation “deeply troubling” and has vowed “to get to the bottom” of them.

Mr Trump appeared to be trying to halt an escalating diplomatic spat with the UK, with Theresa May having made clear that the “trust” between the two nations was at stake as a number of senior political and police figures expressed their dismay at the release of such sensitive information.

Mr Trump said he had instructed the Department of Justice to launch a full investigation into the leaks and “if appropriate, the culprit should be prosecuted to the fullest extent of the law”.

The President’s intervention comes with UK police forces having taken the extraordinary step of having stopped passing information on the investigation into the blast outside of an Ariana Grande concert that killed at least 22 people and left nearly 60 people injured.

“This is until such time as we have assurances that no further unauthorised disclosures will occur,” a counter-terrorism source told Reuters.

Late on Thursday senior UK anti-terror officials said the sharing of intelligence had resumed after those assurances were given.

Ms May raised her concerns with Mr Trump in person ahead of Nato meeting in Brussels – which Mr Trump is attending as part of his first foreign trip – using the set-up of a group photograph to corner the US President. The two then spoke again as they sat next to each other at a Nato working dinner.

The Prime Minister had earlier warned that the “special relationship” could be undermined because of the persistent leaking of intelligence material.

As she arrived in Brussels, Ms May said the attack by suicide bomber Salman Abedi had targeted “innocent and defenceless children and young people”.

Mrs May said: “On the issue of the intelligence-sharing with the USA, we have a special relationship with the USA, it is our deepest defence and security partnership that we have.

“Of course, that partnership is built on trust. And part of that trust is knowing that intelligence can be shared confidently and I will be making clear to President Trump today that intelligence that is shared between law enforcement agencies must be shared securely.”

Manchester explosion in pictures Show all 37 1 /37 Manchester explosion in pictures Manchester explosion in pictures People running down stairs as they attempt to exit the Manchester Arena after a blast, where U.S. singer Ariana Grande had been performing, in Manchester Twitter/@ZACH_BRUCE/ via REUTERS Manchester explosion in pictures Helpers attend to people inside the Manchester Arena after a suspected suicide bomber detonated an explosive device at the end of an Ariana Grande concert, killing 22 people PA wire Manchester explosion in pictures Armed officers guard outside a hotel near the Manchester Arena following reports of an explosion, in Manchester, Britain EPA Manchester explosion in pictures Police officers are seen outside the Manchester Arena, where U.S. singer Ariana Grande had been performing, in Manchester, northern England Reuters Manchester explosion in pictures MANCHESTER, ENGLAND - MAY 23: Police escort members of the public from the Manchester Arena on May 23, 2017 in Manchester, England. An explosion occurred at Manchester Arena as concert goers were leaving the venue after Ariana Grande had performed. Greater Manchester Police have confirmed 19 fatalities and at least 50 injured. (Photo by Christopher Furlong/Getty Images) Getty Images Manchester explosion in pictures MANCHESTER, ENGLAND - Emergency services arrive close to the Manchester Arena on May 23, 2017 in Manchester, England. There have been reports of explosions at Manchester Arena where Ariana Grande had performed this evening. Greater Manchester Police have have confirmed there are fatalities and warned people to stay away from the area. (Photo by Dave Thompson/Getty Images) Getty Images Manchester explosion in pictures MANCHESTER, ENGLAND - MAY 23: Police escort members of the public from the Manchester Arena on May 23, 2017 in Manchester, England. An explosion occurred at Manchester Arena as concert goers were leaving the venue after Ariana Grande had performed. Greater Manchester Police have confirmed 19 fatalities and at least 50 injured. (Photo by Christopher Furlong/Getty Images) Getty Images Manchester explosion in pictures Medics deploy at the scene of a reported explosion during a concert in Manchester, England on May 23, 2017. British police said early May 23 there were "a number of confirmed fatalities" after reports of at least one explosion during a pop concert by US singer Ariana Grande. Ambulances were seen rushing to the Manchester Arena venue and police added in a statement that people should avoid the area / AFP PHOTO / Paul ELLIS (Photo credit should read PAUL ELLIS/AFP/Getty Images) AFP/Getty Images Manchester explosion in pictures Police and fans close to the Manchester Arena, after reports of an explosion Getty Images Manchester explosion in pictures There have been reports of explosions at Manchester Arena where Ariana Grande had performed Getty Images Manchester explosion in pictures Police deploy at scene of explosion in Manchester, England, at a concert in Manchester Arena AFP/Getty Images Manchester explosion in pictures Police stand by a cordoned off street close to the Manchester Arena Getty Images Manchester explosion in pictures Police deploy at scene of explosion in Manchester, England AFP/Getty Images Manchester explosion in pictures Police deploy at scene of a reported explosion during a concert in Manchester, England, on May 23, 2017. British police said early May 23 there were "a number of confirmed fatalities" after reports of at least one explosion during a pop concert by US singer Ariana Grande. Ambulances were seen rushing to the Manchester Arena venue and police added in a statement that people should avoid the area AFP/Getty Images Manchester explosion in pictures An ambulance drives away from the Manchester Arena, where U.S. singer Ariana Grande had been performing, in Manchester Reuters Manchester explosion in pictures Police escort members of the public from the Manchester Arena in Manchester, England. Getty Images Manchester explosion in pictures A woman sits in the street in a blanket near the Manchester Arena as police guard the area following reports of an explosion, in Manchester, Britain EPA Manchester explosion in pictures Two women wrapped in thermal blankets stand near the Manchester Arena, where US singer Ariana Grande had been performing, in Manchester Reuters Manchester explosion in pictures A Royal Logistic Corps (RLC) bomb disposal robot is unloaded outside the Manchester Arena following reports of an explosion, in Manchester. At least 19 people have been confirmed dead and others 50 were injured, authorities said. It is being treated as a terrorist incident until police know otherwise EPA Manchester explosion in pictures A Royal Logistic Corps (RLC) bomb disposal robot is unloaded outside the Manchester Arena following reports of an explosion, in Manchester EPA Manchester explosion in pictures Members of the public receive treatment from emergency service staff at Victoria Railway Station close to the Manchester Arena on May 23, 2017 in Manchester, England. There have been reports of explosions at Manchester Arena where Ariana Grande had performed this evening. Greater Manchester Police have have confirmed there are fatalities and warned people to stay away from the area Getty Images Manchester explosion in pictures Armed police after a suspected terrorist attack at the Manchester Arena at the end of a concert by US star Ariana Grande left 19 dead PA wire Manchester explosion in pictures Emergency services arrive close to the Manchester Arena in Manchester Getty Images Manchester explosion in pictures An amoured police vehicle patrols near Manchester Arena in Manchester Getty Images Manchester explosion in pictures A man carries a young girl on his shoulders near Victoria station in Manchester AFP/Getty Images Manchester explosion in pictures Police officers stand at the Miller Street and Corporation Street Crossroads, in front of the Manchester Arena in Manchester, England Getty Images Manchester explosion in pictures Police block a road near to the Manchester Arena in central Manchester, England AP Manchester explosion in pictures Armed police patrol near Victoria station in Manchester, northwest England. Twenty two people have been killed and dozens injured after a suspected suicide bomber targeted fans leaving a concert of US singer Ariana Grande in Manchester Getty Images Manchester explosion in pictures Police forensic officers leave the Manchester Arena as they investigate the scene of an explosion in Manchester Getty Images Manchester explosion in pictures A forensic officer collects evidence on a walkway between Victoria station and Manchester Arena following a deadly terror attack in Manchester, Getty Images Manchester explosion in pictures A woman and a young girl wearing a t-shirt of US singer Ariana Grande talks to police near Manchester Arena following a deadly terror attack in Manchester, Getty Manchester explosion in pictures epaselect epa05982725 Susan Walton and daughter Katie, 10 (pictured), who attended the concert of Ariana Grande at the Manchester Arena, are seen in Manchester, Britain, 23 May 2017. According to a statement released by the Greater Manchester Police on 23 May 2017, police responded to reports of an explosion at Manchester Arena on 22 May 2017 evening. At least 19 people have been confirmed dead and around 50 others were injured, authorities said. The happening is currently treated as a terrorist incident until police know otherwise. According to reports quoting witnesses, a mass evacuation was prompted after explosions were heard at the end of US singer Ariana Grande's concert in the arena. EPA/NIGEL RODDIS EPA Manchester explosion in pictures Mayor of Greater Manchester Andy Burnham and Manchester City Council Leader Sir Richard Leese speak to the media outside Manchester Town Hall after a suicide bomber killed 22 people, including children, as an explosion tore through fans leaving a pop concert in Manchester Dave Higgens/PA Wire Manchester explosion in pictures The media gather behind a police cordon in Manchester Getty Images Manchester explosion in pictures Flowers left close to the Manchester Arena, the morning after a suicide bomber killed 22 people, including children, as an explosion tore through fans leaving a pop concert in Manchester Danny Lawson/PA Wire Manchester explosion in pictures Ariana Grande concert attendees Karen Moore and her daughter Molly Steed, aged 14, from Derby, leave the Park Inn where they were given refuge after last night's explosion at Manchester Arena Getty Manchester explosion in pictures Signs saying 'We love Manchester' are displayed in a window in Manchester, England Getty Images

Mr Trump also invoked the “special relationship” in saying that he took these alleged breaches seriously, and that the US still values Britain as an important ally. “There is no relationship we cherish more than the special relationship between the United States and the United Kingdom”, he said.

But he was clear that the two nations, Nato and other allies must step up efforts to stop terrorism “in its tracks” as otherwise the “horror you saw in Manchester, and so many other places, will continue forever”.

Mr Trump then appeared to link the controversial issue of migration to the attack. The President has made lowering levels of migration into the US one of his major promises – although the travel ban he has proposed aimed at a number of Muslim-majority nations has been accused of penalising those fleeing war zones.

“You have thousands and thousands of people pouring into our various countries and spreading throughout, and in many cases we have no idea who they are. We must be tough, we must be strong and we must be vigilant,” he said – despite the fact that the Manchester attacker was British-born.

Mr Trump did not confirm that the leaks had come from American intelligence sources. He called the leaks “alleged”, though the information has widely been presumed to have come from US sources since American news organisations have been the first to publish specific details around the investigation and explosion.

US outlets were the first to report the attacker’s name and many details about the victims, leading to condemnation from the Home Secretary Amber Rudd and the Mayor of Manchester, Andy Burnham.

The leaks have continued since, with The New York Times publishing pictures of the bomb and reporting in precise detail how it had been made and detonated. The details came out at a time when British law enforcement officials have been working to determine if there were more potential terrorists planning further attacks beyond the initial attack – and smashing the potential network that assisted in it.

The National Police Chiefs’ Council has condemned the revelations, saying it “undermines our investigations and the confidence of victims, witnesses and their families”.

Lord Carlile, the former Independent Reviewer of Terrorism Legislation, described the leaks as “very unusual and irresponsible” and called for those responsible to be “called to account”.

“Also, it damages decades of confidence between the UK and US services, the cohesion of the ‘Five Eyes’ group, and sharing of information with French, German and other security services,” he said.

Former Metropolitan Police Commissioner Lord Blair said the leak of images from the attack was a “grievous breach” although something similar had happened after the London 7/7 bombings.

Lord Blair, who was head of the Metropolitan Police during the deadly 2005 attacks, told BBC Radio 4’s Today programme: “I’m afraid it just reminds me exactly of what happened after 7/7 when the United States published a complete picture of the way the bombs in 7/7 had been made up.