Prime Minister Theresa May has branded the suicide bomb attack on Manchester as "callous" and "cowardly", as she addressed the UK on Tuesday 23 May. May spoke on the steps of Downing Street after chairing an emergency meeting of the Cabinet Office Briefing Room (COBRA).
Home Secretary Amber Rudd, Foreign Secretary Boris Johnson, Defence Secretary Michael Fallon and Transport Secretary Chris Grayling also attended the meeting, with Greater Manchester Mayor Andy Burnham joining via video link.
May also revealed that the British security services believe they know the identity of the lone attacker, but they will not be releasing his name. May will travel to Manchester later and will also chair another COBRA meeting.
The prime minister's speech comes hours after the attack on an Ariana Grande concert at the 21,000-seat Manchester Arena.
The incident, which happened around 22:30 BST, has left at least 22 people dead and 59 injured.
"It's now beyond doubt that the people of Manchester and of this country have fallen victim to a callous terrorist attack, an attack that targeted some of the youngest people in our country with cold calculation," May said.
"This was among the worst terrorist incidents we have ever experienced in the United Kingdom. Although it is not the first time that Manchester has suffered in this way, it is the worst attack the city has experienced and the worse ever to hit the north of England."
She added: "Today let us remember those who died, and let us celebrate those who helped, safe in the knowledge that the terrorists will never win and our values, our country and our way of life, will always prevail."
All major political parties have suspended their general election campaigns ahead of the 8 June vote in reaction to the attack.
Labour leader Jeremy Corbyn said he was "horrified" by the "horrendous" event. "My thoughts are with families and friends of those who have died and been injured," he said
"Today the whole country will grieve for the people who have lost their lives. I have spoken with Andy Burnham, the mayor of Manchester, who has fully briefed me on the operational response in the city.
"I would like to pay tribute to the emergency services for their bravery and professionalism in dealing with last night's appalling events.
"I have spoken with the prime minister and we have agreed that that all national campaigning in the general election will be suspended until further notice."
US President Donald Trump offered his condolences and support over the phone to May, according to White House Press Secretary Sean Spicer.
"I extend my deepest condolences to those so terribly injured in this terrorist attack and to the many killed and the families, so many families, of the victims. We stand in absolute solidarity with the people of the United Kingdom.
"So many young, beautiful, innocent people living and enjoying their lives murdered by evil losers in life. I won't call them monsters because they would like that term. They would think that that is a great name. I will call them from now on losers because that's what they are.
"This is what I've spent my last days talking about during my trip overseas. Our society can have no tolerance for this continuation of bloodshed. We can not stand a moment longer for the slaughter of innocent people, and in today's attack it was mostly innocent children.
"The terrorists and extremists and those who give the comfort must be driven out from our society for ever. This wicked ideology must be obliterated and innocent life must be protected. All civilised nations must join together to protect innocent life and the sacred right of our citizens to live in safety and in peace."