, several months pregnant with the couple's second child, opted to stay at home.
He said: "Hi everybody. We are at a defining moment in the .
"Tonight is a celebration of each of you here, the vaccinated frontline workers in the audience and the millions of frontline heroes around the world.
"You spent the last year battling courageously and selflessly to protect us all.
"You served and sacrificed, put yourselves in harm's way and with bravery knowing the costs. We owe you an incredible depth of gratitude, thank you.
"We're also coming together because this pandemic cannot end unless we act collectively with an unprecedented commitment to our shared humanity."
The Duke of Sussex called for the vaccine to be distributed "to everyone everywhere," adding "we cannot rest or truly recover until there is fair distribution to every corner of the world."
Harry attended his grandfather Prince Philip's funeral in the UK this month but flew back to Meghan and baby Archie soon after Credit: Getty Selena Gomez was among the hosts Credit: Getty Meghan Markle was billed to appear but Harry flew solo Credit: AFP "None of us should be comfortable thinking that we could be fine when so many others are suffering," he preached.
"In reality, and especially with this pandemic, when any suffer, we all suffer. We must look beyond ourselves with empathy and compassion for those we know, and those we don't.
"We need to lift up all of humanity and make sure that no person or community is left behind.
"What we do in this moment will stand in history and tonight, we stand in solidarity with the millions of families across India who are battling a devastating second wave," he concluded.
The crowd gave Harry a standing ovation for his heartfelt address.
Harry and Meghan are serving as Campaign Chairs of VAX Live, which "aims to inspire vaccine confidence worldwide and help get the Covid-19 vaccines to everyone, everywhere" according to a statement by Global Citizen.
Harry delivered an impassioned speech about vaccine distribution alone Credit: Getty 'None of us should be comfortable thinking that we could be fine when so many others are suffering,' Harry told the crowd Credit: Getty
The event is due to air on television on May 8, and featured a thousands-strong crowd of only fully-vaccinated guests.
Also taking to the stage on Sunday was singer J-Lo who offered a musical performance in a stunning pink gown. She was joined momentarily by her mother, Guadalupe Rodríguez.
The event is hosted by Selena Gomez, and also includes virtual appearances from President Joe Biden and First Lady Jill, in addition to Pope Francis.
President Biden said the US is "working with foreign leaders" in a bid to boost vaccine production worldwide.
Other guests include Oscar-winning actor Ben Affleck, late-night host Jimmy Kimmel and the Dave Grohl-fronted rock group, Foo Fighters.
Gomez told Entertainment Tonight she "geeked out" over the star-studded guest list.
"To me, it's the best award show of the year," the pop star said. "I was equally geeked out when I found out who was going to be here and I was happy that those people decided to join us and spread the word."
J-Lo offered a musical performance in a stunning pink gown Credit: Getty She was joined momentarily by her mother, Guadalupe Rodríguez Credit: Getty Vax Live is being billed as an event to "reunite the world" with performances from a host of stars.
So-Fi Stadium has a capacity of 70,000 spectators but it's not known how many attended the show.
Those in attendance were required to have their second Covid-19 vaccine dose no later than April 18.
As campaign chairs, Harry and Meghan will lead a drive to raise money for COVAX - a vaccine-sharing program co-led by the World Health Organization.
The event raised $53.8million for COVAX - an initiative designed to provide vaccines for low and middle-income countries.
Organizers say it was enough to purchase over 10million vaccine doses.
Speaking on their Archwell site, Meghan and Harry said: "Over the past year, our world has experienced pain, loss, and struggle—together. Now we need to recover and heal—together. We can’t leave anybody behind.
"We will all benefit, we will all be safer, when everyone, everywhere has equal access to the vaccine.
"We must pursue equitable vaccine distribution, and in that, restore faith in our common humanity. This mission couldn’t be more critical or important.”
Other guests include Oscar-winning actor Ben Affleck and late-night host Jimmy Kimmel Credit: Getty Joe and Jill Biden appeared virtually for the event Credit: Getty Pope Francis also made an address in pre-recorded remarks Credit: AFP Harry received a standing ovation from the thousands-strong crowd Credit: Getty Actress Olivia Munn is pictured on stage on Sunday night Credit: Getty Eddie Vedder performs onstage during Global Citizen VAX LIVE: The Concert To Reunite The World Credit: Getty It is the glitziest event the pair have taken part in since they left the UK for the US last year when they stepped down as senior royals.
In January last year the pair made the shock announcement they planned to "step back" from royal duties.
They wrote: "After many months of reflection and internal discussions, we have chosen to make a transition this year in starting to carve out a progressive new role within this institution.
"We intend to step back as ‘senior’ members of the Royal Family and work to become financially independent, while continuing to fully support Her Majesty The Queen."
It came after The Sun revealed they were due to discuss plans to move abroad.
Meghan has still not made a public appearance since the couple's explosive tell-all interview with Oprah Winfrey in March.
Multiple organisations have thrown their weight behind the campaign - including WHO and European Commission President Ursula von der Leyen.
The event will be streamed at 8pm ET time in the US on ABC, CBS and YouTube.
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