Sir Elton John is escorted off stage mid-way through a February 16 gig in New Zealand after being diagnosed with walking pneumonia. (Twitter/EltonJohnOfficial)

Sir Elton John has broken down in tears and cut short a New Zealand gig to be escorted off stage by medics.

The singer, 72, revealed that he had been diagnosed the same day with walking pneumonia.

An emotional Elton broke down in tears at the piano mid-way through the gig and told the crowd: “I’ve got to go. I’m sorry.”

“I’ve just completely lost my voice. I can’t sing,” Sir Elton said.

The crowd gave him a rapturous standing ovation as he was escorted off stage by several people.

“I want to thank everyone who attended the #EltonFarewellTour gig in Auckland tonight. I was diagnosed with walking pneumonia earlier today, but I was determined to give you the best show humanly possible,” the singer tweeted soon after the gig.

Walking pneumonia is a type of lung infection that can be caused by bacteria or viruses.

According to the BBC, it is less severe than other types of pneumonia, with most sufferers not requiring medical attention. Symptoms are comparable to those of a bad cold, often including a cough, chest pain, a sore throat and a headache.

Shortly after cutting the Auckland gig short, Elton John wrote on Instagram to thank his fans.

“I played and sang my heart out, until my voice could sing no more,” he said.

“I’m disappointed, deeply upset and sorry. I gave it all I had. Thank-you so much for your extraordinary support and all the love you showed me during tonight’s performance. I am eternally grateful. Love, Elton xx.”

Fans were quick to show their support for the singer online, with one person tweeting: “Elton, tonight you were incredible. To perform the way you did, was just indescribable – the fact you continued to push through and sing (and sing incredibly) even when you couldn’t talk is just phenomenal.

“Thank you for everything, you are a true inspiration.”

The New Zealand gig is part of the star’s global farewell tour.