The Miss Universe 2015 contest has ended in confusion and disarray after the host mistakenly named the wrong woman as the winner.

Ariadna Gutierrez Arevalo from Colombia had already been crowned and was standing on stage to cheers from the Las Vegas audience when mortified host Steve Harvey returned to announce the error.

“OK, folks, um, I have to apologize,” he said, walking back on stage while Arevalo was proudly waving to fans, holding the winner’s bouquet and wearing the Miss Universe sash. “The first runner-up is Colombia,” he went on, “Miss Universe 2015 is Philippines.”

The camera panned straight to a stunned Miss Philippines, Pia Alonzo Wurtzbach, who started slowly walking to the front of the stage. For a few awkward moments the two women stood side by side, in front of a TV audience of millions from around the world, before Harvey explained that he read the card naming the winner and runner-up in the wrong order.

“I will take responsibility for this, it was my mistake,” he told the crowd. “It’s on the card ... horrible mistake, but I can show it to you right here,” he said, holding up the card.

“It is my mistake, but it’s still a great night.”

“Please don’t hold it against the ladies, please don’t. I feel so badly but it’s still a great night.”

As he spoke, a former Miss Universe winner quickly removed the crown from Arevalo and placed it on Wurtzbach. The broadcast ended moments later.

The reaction on social media was swift, with viewers expressing dismay at the “fail of the decade”.