"Russell wanted to do something special for Katy to show her how much she means to him," the Sun quoted an insider as saying. The source added: "They wanted to take part in a traditional ceremony and thought there was no better time than on New Year's Eve. The ceremony is usually used to bless new couples in the hope it might lead them toward marriage. If Russell can see out a year without straying, this one could go the distance. "
The ritual took place on the "blue moon" day, the 13th full moon in the calendar year, which occurs every two or three years. An excited Perry Tweeted later: "Happy New Years everyone... Under a blue moon."