'Are you sure you want to marry us?'

Not many couples will have asked a priest that just before their wedding, but the circumstances were a little unusual.

The happy couple were stewards aboard the papal plane carrying Pope Francis on the next leg of what so far has been quite a difficult trip to South America. And the celebrant was the Pope himself, who was about to conduct what may be the world's first airborne wedding – and certainly the first celebrated by a Pope.

Paula Podest, 39, and Carlos Ciufardi, 41, have been together for more than 10 years and have been civilly married since 2010. They asked the Pope for his blessing on the flight and as they posed for a picture he asked them whether they had ever been married in church. On hearing they hadn't – an earthquake destroyed the church they were to marry in just before the ceremony – Francis immediately offered to marry them there and then.

They told the journalists on the plane what had happened. 'He asked us if we were married, I said "no" because of the earthquake, and he said, "Well, I'll marry you,"' Ciufardi said.

They said, 'Are you sure?' whereupon Francis drafted the CEO of the airline to act as one of the witnesses. To ensure the validity of the licence he asked the cardinals who were with him to draft it.

'He held our hands, blessed the rings, and he married us in the name of God,' Ciufardi said according to Crux.

'What he said to us is very important: "This is the sacrament the world needs, the sacrament of marriage. Hopefully, this will motivate couples around the world to get married."'

Speaking of the rings, Francis said that they should not be too tight, because 'they would be a torture' nor too loose, or they might be lost.