Both the Britain's Got Talent viewers and judging panel were left stunned after Simon Cowell demonstrated his David Attenborough impression on Sunday night.

The music mogul, 64, jokingly adopted the beloved presenter's famous voice he uses to narrate his nature documentaries, to give feedback to one act during auditions.

Simon, Amanda Holden, Alesha Dixon and Bruno Tonioli were gobsmacked as Geneviève Côté showed off her talent of creating nature sounds.

The entertainer, 60, travelled from Canada to audition, with hosts Ant McPartlin and Dec Donnelly assuming she was going to sing.

However, instead she did a number of incredible sound effects and animal impressions to match nature clips behind her, accompanied by melodic background music.

A stunned Amanda said: 'Is she doing the noise? I wasn't expecting that!' while Ant declared: 'Oh my God she's bloody great!'

When it came time to give feedback, Bruno said: 'I was so mesmerised, I felt nature coming out of your body, expression of nature, the force of nature, you are a force of nature, what can I say!'

Amanda added: 'It was one of the most spiritual experiences I think I've ever felt, it was so stunning. I've never seen anything like it in my life!'

While Alesha echoed: 'I was utterly gobsmacked throughout that whole performance, just sat here in a trance, mesmerised by you!'

When it came for Simon's thoughts he gushed: 'This was absolutely unbelievably good. Your voice is sensational! Everything about that, that was perfection.'

He then put on David's voice and pretended to be narrating a documentary, saying: 'I think we are witnessing something truly special.'

The audience cheered at the impersonation, while a shocked Alesha asked: 'How'd he do that?'

Amanda broke into laughter and commented: 'He's so good' while Bruno jumped up to declare: 'That is fantastic!'

Viewers watching at home were also taken by surprise, taking to social media to write: 'Didn’t know Simon Cowell could do impressions!' while another quipped: 'I expect David Attenborough gave that his own golden buzzer'.

Simon previously displayed his impression of David, 97, on the show in 2022, while judging mini-environmentalist Aneeshwar Kunchala in the semi-final.

The then seven-year-old read out a poem about the importance of looking after the planet, to glowing praise.

Simon said: 'It was pure, utter magic – and let’s remember you are seven years old, and there was so much to remember and to time everything with the images… Here’s a conversation I think is going to happen from [sic] Mr Attenborough.

He then adopted David's distinct tones and said: 'Aneeshwar, I would like you to take over from me doing Blue Planet.'

Meanwhile, Geneviève got four yeses off the spellbound judges and sailed through to the next round.

However, she also sparked controversy as it is not her first time performing on a Got Talent contest.

Eagle-eyed fans recognised her from three previous international series over the past year alone, where she got two elusive Golden Buzzers.

In March 2023, Geneviève appeared on Canada's Got Talent and left the judges so awestruck that Howie Mandel gave her his Golden Buzzer.

She made it all the way to the finals, before being beaten by dance group Conversion.

However, her performance definitely left an impression on Howie as he brought her to be part of his team on America's Got Talent: Fantasy League this January.

And in between those two appearances, Geneviève also auditioned for France's version of the show, 'La France a un incroyable talent'.

She received judge Karine Le Marchland's Golden Buzzer and made it through to the semi-finals, but was then eliminated. 

Britain's Got Talent does allow anyone to take part in the competition regardless of their experience and previous participation. 

However ITV viewers have become increasingly agitated over the years over participants being given multiple chances of shows of stardom.

It comes after the show returned to screens on Saturday night, and is seemingly already off to a promising start.

According to overnight figures, the launch episode of series 17 saw an average of 5 million viewers tuning in, with a peak of 5.8 million.

The ratings make it ITV’s biggest overnight audience of the year so far since The FA Cup quarter final match last month, which garnered 5.5 million viewers.

While the show raked in 642,000 viewers aged between 16 and 34, roughly a 42 per cent share of viewing.

But despite gaining strong viewers for the broadcaster, the ratings were still down from last year's launch episode. 

The 2023 opener peaked at 6.2million viewers, which ITV said was its highest rated programme of the year.

It reflects a steady decline in viewings for the show, after the 2022 series premiere saw a TV audience peak of 7.2 million, following a two year break due to Covid.