He may have given a choir group the surprise of their lives, but it was Michael Bublé who was left even more stunned after turning up to a London venue while promoting his latest album.

The Canadian crooner thought he was embarking on routine promotional activities, but instead, London’s West End Gospel Choir invited him to perform one of his favourite tracks from Higher, “Bring It On Home to Me” – a song he jokes that Ryan Reynolds, Celine Dion and Alanis Morrisette have all declared one his greatest recordings.

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“When I walked in, I was overwhelmed,” Bublé, 46, recounted to ET Canada ahead of kicking off the U.S. and Canadian legs of his Higher Tour in Georgia on Monday night. “That’s a song I was so proud of and it brings me so much joy. When I heard them doing it, I was like, ‘I get to sing this?’ I was really nervous because it was so unexpected.”

Photo: Warner Music
Photo: Warner Music

In ET Canada’s exclusive video of the performance, the choir’s shown singing (thinking they’re being filmed for Bublé’s social media platforms) then applaud and laugh as Bublé suddenly walks in.

“I feel the same way right now!” he responds.

Choirmaster Nathaniel Morrison, who was the only performer in on the surprise, then invites Bublé to join them.

“I’m gonna sing with you?” Bublé asks, seemingly perplexed by the idea. “Sh**. Yes!”

“It’s a song you might know,” Morrison replies. “If you feel the spirit, just join in.”

Bublé’s jaw drops as Morrison kicks off “Bring It On Home To Me,” a song by late musician Sam Cooke, that he covers on Higher, which was released in March. Eventually joining in, the British Columbia native pauses to declare, “This is the best day ever!”

“You guys, I have to tell you – I’ve been freaking out,” he says after hugging each singer afterwards. “When I recorded this song, it was the greatest thing I ever recorded in my life and I’ve been driving people crazy.”

“I [was] doing all the TV shows and doing the pop songs and was like, ‘How am I ever going to make a moment of this and let people see how beautiful this is?’” he continues, after becoming emotional. “This is the moment. You guys gave me the moment.”

Photo: Warner Music
Photo: Warner Music

Quizzed about the powerful performance afterwards, Bublé remains moved.

“That was truly one of the greatest moments of my life,” he enthuses. “I had no idea what I was walking into – the most beautiful voices. This incredible choir that worked so hard to learn this song and allow me to join them. It was my privilege, my joy, my pleasure and I hope that when I come do a show here that they’ll come with me, so we can bring this to you live and you can feel what we felt here today.”

While speaking to ET Canada, Bublé further explained the significance of the track.

“I’ve recorded so many songs in my career, but I don’t think I’ve ever nailed it the way we nailed that recording,” he said. “If you have a chance, go listen to ‘Bring It On Home To Me’ and if you don’t like it, you have no soul. And that’s okay – I will hold you and hug you.”

“But go and ask Ryan Reynolds, Celine Dion, Alanis Morrissette, Seth Rogen, Ryan Gosling – all of them say it is one of the greatest songs ever recorded by me,” he continued, later noting he finds Rogen “very sexy.” “Ask Sarah McLachlan. I’m lying. None of those people have said it’s their favourite song. But I would pay them if they did, so if any of you are watching, I will give you American dollars if you repeat what I just said about me!”

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Bublé, who’s preparing to welcome his fourth child with 34-year-old wife Luisana Lopilato, is now looking forward to performing the song on home ground when the Canadian run of his Higher Tour commences in Vancouver on October 1. After getting his fix of local junk food like Coffee Crisps, ketchup chips and Timbits, he’ll hit venues across the country and urges everyone to check out what he describes as, “the best show on earth.”

Photo: Warner Music
Photo: Warner Music

“I’ve put so much into making sure this show is new, unique and incredibly-exciting and I think I’m going to make Canada proud of their boy,” he said. “The reason I’m good at what I do is because I love who I do it for and I’ve put a lot of time, love and effort into making this show special. If you miss it, you’re missing out.”

“I really hope people get to see it because I think this is one of those shows that doesn’t come around often,” he continued. “It’s one of those cool things [where] you can bring your kids, your grandma and [everyone’s] going to love it.”