Manchester remembers 22 May bomb massacre

Salman Abedi, a British man of Libyan heritage, detonated a bomb outside the venue following a concert by pop idol Ariana Grande, killing himself and concertgoers, many of them teenagers. The Islamic State group claimed the attack.

"The targeting of the young and innocent as they enjoyed a carefree night out... was an act of sickening cowardice," Theresa May wrote in the city's local paper the Manchester Evening News. 

"It was designed to strike at the heart of our values and our way of life in one of our most vibrant cities, with the aim of breaking our resolve and dividing us. It failed."

She said that "such appalling acts of wickedness" would strengthen the UK's resolve "to defeat such twisted ideologies and beliefs".

Churches in York, Liverpool and Glasgow will also screen the service.

It will incorporate a minute of silence at 2.30pm (1:30pm GMT), which will also be marked at British government buildings nationwide.

More than 3,000 singers from local choirs, including a group who were at the arena on the night, will join forces later Tuesday at a "Manchester together" event in a city centre square.

It will feature half an hour of communal singing.

Mayor of Greater Manchester Andy Burnham told BBC Radio that all those impacted would be "at the very forefront of our minds" during the day.

"We're stronger than we were, we're more together and there is a more palpable sense of community spirit, but underneath the scars are very real and they're very deep," he said.

"We're a city in recovery and we've still got a long way to go."

Grande shared a message of support for those affected. 

"I love you with all of me and am sending you all of the light and warmth I have to offer on this challenging day," she wrote.

A spate of militant attacks hit the UK last year - one in Manchester and four in London. These attacks included bombings and deadly violence using vehicles and knives.