Declan Donnelly collapses on stage in unearthed Ant and Dec clip ‘following mystery illness’

DECLAN Donnelly 'collapsed' on the studio floor with a 'mystery illness' in a resurfaced clip from his SM:TV Live days.

The Geordie telly host, 46, was performing a dance with his co-stars Ant McPartlin and Cat Deeley when he suddenly appeared unwell.

Joined on either side by 90s pop bands Westlife and B*Witched, Dec then put his hand to his mouth and fell on the floor.

As Ant momentarily continued with the show, a member of the crew rushed in to tend to the apparently stricken star.

"What's he doing?" Cat asked. Ant chipped in: "Is he alright?"

Suddenly, there was a commotion in the studio and Cat yelled, "Can somebody get the nurse" before the kids' show went off air.

An ITV holding message appeared on screen, stating: "Sorry about the fault. We're working to restore your programme as soon as possible."

As it all happened before the days of social media, worried viewers began bombarding the SM:TV phone lines with calls of concern.

But seconds later, the popular show returned and Dec was back upright and appearing well.

He told fans: "Something happened here in the studio. I just...I just keeled over. I collapsed. I wasn't feeling too well.

"Thanks for all your calls of concern. There's no need to be alarmed.

"I'd just like to say happy April Fools' Day."

Dec then smiled and winked as the camera zoomed in on his face.

The cheeky clip was aired during Ant and Dec's 30 Greatest Moments.

The one-off Channel 5 programme featured the best bits of the duo's long career in showbiz.