President Donald Trump told leaders of the NATO alliance on Thursday that the Manchester bombing that killed 22 earlier this week demonstrates the depths of the evils of terrorism.

After leading a moment of silence at the NATO headquarters in Brussels for victims of Monday night's bombing, Trump said that attacks will continue unless steps are taken to counter terrorism strikes.

He said that the United States would never stop fighting terrorism, calling the Manchester attacks 'savage' and 'barbaric'.

Meanwhile he called the alleged US intelligence leaks 'deeply troubling' and called for US officials to launch a full investigation hours before British authorities announced they were once again sharing information with the US.

After leading a moment of silence for victims of Monday night's bombing, President Donald Trump said that attacks will continue unless steps are taken to counter terrorism strikes

Pictured above, (Front row from L) Belgian Prime Minister Charles Michel, King Philippe - Filip of Belgium, NATO Secretary General Jens Stoltenberg, US President Donald Trump, Britain's Prime Minister Theresa May, (second row from L) French President Emmanuel Macron, German Chancellor Angela Merkel, Greek Prime Minister Alexis Tsipras, Hungary's Prime Minister Viktor Orban, Iceland's Prime Minister Bjarni Benediktsson, (third row from L) Norway's Prime Minister Erna Solberg, Polish President Andrzej Duda, Portuguese Prime Minister Antonio Costa, Romanian President Klaus Werner Iohannis, Slovakia's President Andrej Kiska

Trump, pictured alongside NATO Secretary General Jens Stoltenberg during the moment of silence, said that the United States would never stop fighting terrorism, calling the Manchester attacks 'savage' and 'barbaric'

Trump also lectured members of the NATO alliance to pay their fair share on defense during the ceremony

'Terrorism must be stopped or ... the horror you saw in Manchester and so many other places will continue forever,' Trump said, referring to Monday's suicide bomb in the northern English city that killed 22 people, including children.

His comments came after he unveiled a memorial to the September 11, 2001, attacks on New York and Washington at the NATO headquarters.

Meanwhile the President went viral for the wrong reasons when he appeared to 'shove' Montenegro Prime Minister Duško Marković.

It was during a NATO 'family photo' planned with assigned positions for 31 people: the 28 heads of state and the Montenegrin, plus Stoltenberg, and the king and prime minister of Belgium, the host country.

Trump, Stoltenberg and the Belgians were set to be front-row center, with British Prime Minister Theresa May on Trump's other side.

NATO protocol calls for the participants to be alphabetical order of country, with a few exceptions, including the U.S. having a place of honor in the front, next to the UK.

Meanwhile Trump told NATO leaders that the unveiling is 'a day for both remembrance and resolve'.

'We will never waiver in our determination to defeat terrorism and achieve lasting security, prosperity and peace,' he said.

Trump also lectured Nato leaders on their open borders, tying terror attacks like last week's carnage in the United Kingdom to the unchecked flow of migrants throughout Europe.

He said: '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.'

'The NATO of the future must include a great focus on terrorism and immigration,' he said.

Trump acted like nothing had happened after pushing his way to the front for the NATO 'family photo'

The official seating chart put Trump (US) in the front row and Marković ('MON') in the corner. NATO protocol calls for alphabetical order with a few exceptions, including the U.S. having a place of honor in the front, next to the UK

Trump hammered home the same anti-terror themes he has flogged since his inaugural foreign trip began last Saturday – saying of suicide bombers and other jihadis that 'wherever they exist in our societies, we must drive them out and never, ever let them back in.'

Trump said he has been 'very, very direct' with NATO Secretary General Jens Stoltenberg and other nations 'in saying that NATO members must finally contribute their fair share and meet their financial obligations.'

'But 23 of the 28 member nations are still not paying what they should be paying, and what they are supposed to be paying, for their defense.'

'This is not fair to the people and taxpayers of the United States,' he said, 'and many of these nations owe massive amounts of money for past years, and not paying in those past years.'

TRUMP'S SPEECH TO NATO On the 'evils of terrorism': 'Innocent little girls and so many others were horribly murdered and badly injured whilst attending a concert. 'Beautiful lives with so much great potential, torn from their families for ever and ever. It was a barbaric and vicious attack upon our civilisation. 'All people who cherish life must unite in finding, exposing and removing these killers and extremists, and yes, losers, they are losers. 'Wherever they exist in our societies we must drive them out and never, ever let them back in.' On 'unchecked immigration in Europe: 'Terrorism must be stopped in its tracks or the horror we saw in Manchester and so many other places will continue forever. '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. 'The Nato of the future must include a great focus on terrorism and immigration, as well as on threats from Russia and on Nato's eastern and southern borders.' Donald Trump, left, and Theresa May, right, were believed to have discussed the issue of US intelligence leaks on the Manchester bombing yesterday in Brussels, pictured On the US intelligence 'leaks': 'The alleged leaks coming out of government agencies are deeply troubling. These leaks have been going on for a long time and my Administration will get to the bottom of this. 'The leaks of sensitive information pose a grave threat to our national security. 'I am asking the Department of Justice and other relevant agencies to launch a complete review of this matter, and if appropriate, the culprit should be prosecuted to the fullest extent of the law. 'There is no relationship we cherish more than the Special Relationship between the United States and the United Kingdom.' On NATO members's financial contributions: 'I have been very very direct with [Nato general secretary] Jens Stoltenberg and members of the alliance in saying Nato members must finally contribute their fair share and meet their financial obligations. 'But 23 of the 28 member nations are still not paying what they should be paying and what they're supposed to be paying for their defence. 'This is not fair to the people and taxpayers of the United States. Many of these nations owe massive amounts of money from past years. 'Over the last eight years, the United States spent more on defence than all other Nato countries combined. 'We have to make up for the many years lost – two per cent is the bare minimum for confronting today's very real and very vicious threats. 'If NATO countries made their full and complete contributions, then NATO would be even stronger than it is today, especially from the threat of terrorism.' Advertisement

Trump said the U.S. has spent more money on defense in the past eight years than the combined spending of all other NATO members.

And he called on them to make good on pledges to spend at least 2 per cent of their gross domestic product – 'the bare minimum,' he said – on defense, including becoming current with their NATO dues.

'If NATO countries made their full and complete contributions, then NATO would be even stronger than it is today – especially from the threat of terrorism,' Trump insisted.'

British police have made significant arrests and have uncovered important items as they investigate the suicide bomb attack at an Ariana Grande concert in Manchester, the head of the city's police said.

Greater Manchester police are holding eight people in custody, having released a woman without charge on Thursday.

British police have made significant arrests and have uncovered important items as they investigate the suicide bomb attack at an Ariana Grande concert in Manchester, the head of the city's police said

Greater Manchester police are holding eight people in custody in connection to the attack (a scene from the attack pictured above), having released a woman without charge on Thursday

Salman Abedi, a 22-year-old British-born man with Libyan parents, blew himself up on Monday night at the Manchester Arena indoor venue after a concert by U.S. singer Ariana Grande, whose fans are mostly children and teenagers.

The explosion killed 22 people, ranging from an eight-year-old schoolgirl to parents who had come to pick up their children.

With the official threat level raised to 'critical', meaning a further attack could be imminent, troops have been deployed to free up police, and armed officers patrolled trains for the first time in Britain.

Police, who believe Abedi was part of a network, are holding eight people in custody in connection with the attack.

'I want to reassure people that the arrests that we have made are significant, and initial searches of premises have revealed items that we believe are very important to the investigation,' Manchester's police chief Ian Hopkins said.

'These searches will take several days to complete.'

Trump said on Thursday that it was 'deeply troubling' that leaks to the US media about the Manchester suicide bombing would be investigated, after irate British police stopped sharing information with US agencies.

His comments came after he unveiled a memorial to the September 11, 2001, attacks on New York and Washington at the NATO headquarters

Trump (pictured walking past Britain's Prime Minister Theresa May) told NATO leaders that the unveiling is 'a day for both remembrance and resolve'

British Prime Minister Theresa May said earlier she would tell Trump that intelligence shared between their two countries had to remain secure, in a rare public show of dissatisfaction with Britain's closest security ally.

'The alleged leaks coming out of government agencies are deeply troubling,' Trump said in a statement released after he arrived in Brussels for a NATO summit, also attended by May.

'I am asking the Department of Justice and other relevant agencies to launch a complete review of this matter, and if appropriate, the culprit should be prosecuted to the fullest extent of the law.'

It comes as British police have reopened information-sharing ties with the US following a spat over leaked evidence from the Manchester bombing, police chiefs said.

SECRET DETAILS THAT AMERICANS LET SLIP British spies and police were forced to suspend sharing intelligence with the US about the Manchester attack. The unprecedented decision to interrupt the UK’s closest intelligence arrangement with any country came after a series of highly sensitive leaks from America’s law enforcement agencies to US media. Aside from damaging the trust between the two countries, UK security agencies believe the leaks undermined their work and harmed their investigations. Here is the list of leaks from the attack: As the attack unfolded, US ‘law enforcement sources’ briefed TV network CBS that a suicide bomber carried out the attack. Two sources told them about how the bomber travelled by train to Victoria station and how the explosions contained nails. Another broadcaster, NBC, was also given details about the attack method.

Bomber Salman Abedi’s name was provided to US media. UK police did not release it initially because they wanted to get ahead in the investigation. But it was reported on American breakfast television at least six hours before British authorities released it.

The fact the bomber was identified by a bank card in his pocket was leaked to NBC. Citing a US intelligence official, it reported members of the bomber’s family had warned security officials about him in the past, saying he was ‘dangerous’. The official said Abedi likely ‘had help’ making the ‘big and sophisticated bomb’.

According to the broadcaster, a US intelligence official, said to have ‘direct knowledge of the investigation’, revealed how Abedi had ties to Al Qaeda and had received terrorist training abroad.

Photographs taken from the crime scene were leaked to the New York Times. The images showed blood-smeared fragments from the bomb, the backpack used to conceal it and a diagram showing where the bodies were.

Authorities revealed to ABC News how detectives apparently found a bomb-making workshop in Abedi’s home. Details included how he apparently stockpiled enough chemicals to make more bombs. Advertisement

Mark Rowley, the country's most senior counter-terrorism officer, confirmed they had 'received fresh assurances' from their foreign counterparts and were now 'working closely' with them.

Mr Rowley said: 'We greatly value the crucial relationship with our trusted partners around the world so we can collaborate and share sensitive information to defeat terrorism and protect the public at home and abroad.

'While we do not usually comment on information-sharing arrangements with international law enforcement organisations, we want to emphasise that, having received fresh assurances, we are now working closely with our key partners around the world including all those in the Five Eyes intelligence alliance.'

Lewis Lukens, acting US ambassador to the UK, yesterday apologised for the ‘reprehensible’ leaks, thought to have stemmed from material shared with the FBI.

He added: ‘At all levels of government we have heard the message loud and clear from Her Majesty’s Government and we agree with their concerns and we’re determined to take action.’

The Home Secretary said she was ‘confident’ the leaks would stop and the suspension of intelligence-sharing would be temporary.

Miss Rudd added: ‘Greater Manchester Police and the counter-terrorism police have taken a view. We hope that it is just going to be temporary, but it has been worrying, the leaks. But we are confident that will now end.’

In addition to tackling terrorism, Trump used his first NATO summit to urge the alliance to do more to tackle immigration and Russian threats.

'The NATO of the future must include a great focus on terrorism and immigration as well as threats from Russia and NATO's eastern and southern borders,' Trump said.

Trump does, however, stand united with other NATO countries in defending all members of the Western military alliance, a senior White House official said on Thursday, despite the president making no mention of NATO's Article V in a speech.

'It's the core of the alliance,' the official said after Trump gave a speech to fellow NATO leaders in Brussels.

NATO's founding treaty states that an attack on one ally is an attack on all, but Trump questioned that in his election campaign. Article 5 has only been activated once, after 9/11.

Trump has so far refused to personally commit to abiding by Article 5, which commits allies to defend any of the 28 members that come under attack.

Press Secretary Sean Spicer, however, said that 'It goes without saying' that Trump's presence at the event underscores the White House's 'commitments and treaty obligations'.

US Secretary of State Rex Tillerson said Wednesday that 'of course' the United States supports Article 5.

But European Council President Donald Tusk indicated there were divisions between Europe and the US on trade and other issues.

Trump used his first NATO summit to urge the alliance to do more to tackle immigration and Russian threats

Trump, second left, speaks with NATO Secretary General Jens Stoltenberg, left, accompanied by Croatian President Kalinda Grabar-Kitarovic, second right, and Netherlands' Prime Minister Mark Rutte during a NATO summit of heads of state and government in Brussels

Trump talks with British Prime Minister Theresa May during a transfer ceremony at the new NATO headquarters

He said: 'We agreed on many areas, first and foremost on counter-terrorism,' after he and EU chief executive Jean-Claude Juncker met Trump for over an hour.

'But some issues remain open, like climate and trade.'

European leaders have been urging Trump not to abandon the U.S. commitment to cutting greenhouse gas emissions made when his predecessor Barack Obama signed up to the U.N. Paris accord.

Tusk also said he did not feel he and Trump were 'on exactly the same page' in terms of dealing with Russian President Vladimir Putin, although they agreed on efforts to end conflict in Ukraine which the West blames on Moscow and which has resulted in both EU and U.S. economic sanctions on Russia.

A spokeswoman for Juncker, the president of the European Commission which had been negotiating an ambitious free trade deal with Washington before Trump's upset election victory, said the two sides would work to increase trade.

'Intensifying trade cooperation ... is a win-win situation for both sides,' the EU spokeswoman said.

'It was agreed to start work on a joint action plan on trade.'

Juncker declined comment on whether talks in the coming weeks might revive the TTIP trade deal.

Trump has made clear his dislike of multilateral trade agreements, pulling out of the TPP agreement with Asian states.

However, European leaders, including German Chancellor Angela Merkel, have suggested he is warming to trade talks with the EU, which unifies trade rules for all 28 states.

Trump irritated EU leaders during his election campaign last year by hailing Brexit and suggesting other countries might follow Britain out of the 28-nation bloc.

Eurosceptic leaders said he would offer Britain a free trade deal once it left.

However, EU officials believe Trump has come to appreciate more since taking office the value of European integration to U.S. interests.

U.S. businesses have taken advantage of its single market to reduce the costs of exporting to Europe.

An EU source said Trump had told Tusk and Juncker he was now worried that Americans may lose jobs as a result of Britain leaving the EU in 2019:

He 'expressed concern that jobs in the U.S. would be lost because of Brexit', the source said.

Trump shoves European leader aside to find his place at the center of NATO group photo

By David Martosko, US Political Editor for DailyMail.com in Brussels

A Trump moment went viral for the wrong reason on Thursday as he and the leaders of 27 other NATO member countries assembled for a photo at the treaty organization's gleaming new Brussels, Belgium headquarters.

As Trump made his way through the group to take his position in the front row next to Secretary General Jens Stoltenberg, Montenegro's Prime Minister Duško Marković was in his way.

So Trump put his hand on Marković's upper arm and shoved him aside.

COMING THROUGH: Donald Trump saw Montenegro's prime minister in his way before a 'family photo' of NATO leaders, so he shoved him aside

The U.S. president tried to be nonchalant, but the resulting moment caught fire on Twitter

Montenegro is not yet a NATO country. Its membership becomes official on June 5.

The 'family photo' was planned with assigned positions for 31 people: the 28 heads of state and the Montenegrin, plus Stoltenberg, and the king and prime minister of Belgium, the host country.

Trump, Stoltenberg and the Belgians were set to be front-row center, with British Prime Minister Theresa May on Trump's other side.

Marković – the new guy – was placed in the back row on the far right end.

Trump was seen as a party pooper at the NATO summit, lecturing his fellow heads of state about their deadbeat nature and the need to secure their borders in the fight against terror.

Trump had earlier put his weight behind his first handshake with France's new president, Emmanuel Macron, gripping and torquing his way on Thursday through the crucial moment in their budding relationship.

They shook hands for a full five seconds while camera shutters clicked, pumping their fists 16 times in a seeming battle of the phalanges.

Donald Trump and French President Emmanuel Macron pumped fists for a full five seconds on Thursday in Brussels as the two leaders seemed to be locked into a battle of the phalanges

Keep pumping: The grip and grin went on for a solid five seconds as Trump met Macron, the new French leader for the first time

Their knuckles turned white, their eyes met, their jaws clenched.

Trump ultimately released first, leaving Macron to hang on to his open hand.

Macron, the youngest French head of state since Napoleon, has held office for just 11 days.

But Trump, who is fond of winners and considers 'loser' to be the ultimate insult for murderous terrorists, seemed to give him his stamp of approval – moments before the younger president brought up global warming to jab him.

Just a month ago, he suggested that far-right French presidential candidate Marine Le Pen was the 'strongest' candidate 'on borders, and she's the strongest on what's been going on in France – a reference to terrorism.

Thursday he was firmly on Team Macron.

'It is my great honor to be with the newly elected president of France, who ran an incredible campaign and had a tremendous victory,' he said. 'All over the world they're talking about it.'

'We have a lot to discuss,' Trump added, 'including terrorism and other things. Congratulations. Great job.'