The British comic star decided to have the blessing – which grants the recipients luck and divine happiness - just before midnight on New Year's Eve (31.12.09) as a declaration of his love for the 'I Kissed A Girl' singer while the pair were holidaying in India.
A source said: "Russell wanted to do something special for Katy to show her how much she means to him.
"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."
Russell, 34, and Katy, 25, both wore traditional Indian outfits for the ceremony – which took place at the foot of a mountain.
Legendary lothario Russell has turned his back on his womanising ways since meeting Katy, and announced just before he went to India that he was a reformed man.
He said: "Tonight I turned off my famous, hedonistic hot-tub, a monumental event. I did it for climate change. In every sense."