The couple got married in the morning at a resort hotel.
While the 30-year-old Ghajini actress donned a white gown, the groom opted for a black suit and bow tie.
Gracing the occasion was Asin-Rahul's close friend and superstar Akshay Kumar, who also played cupid for the couple.
He shared a picture on Twitter and wrote,"Wishing d Happy Couple,Asin & Rahul a lifetime of Love & Adventures, indeed made 4 each other. Love & prayers always."
"It was a beautiful wedding. Everyone looked amazing. Akshay was present. It was Asin's idea to have a Catholic wedding. We all are very happy," said a close relative of Rahul.
Delhi-based music group Elohim Worship band performed at the wedding.
"Everything went great at the wedding. We played some 2-3 songs. Asin looked beautiful in her white gown. We had a rehearsal yesterday," said a band member.
The wedding rituals began around 11 and went on for about 30 minutes.
The couple had a second ceremony as per Hindu rituals in the evening at the same venue.
"The time for the wedding was 7 pm and it included jaimala and pheras," said one of the priests invited to solemnise the marriage. Around 200 people had been invited by Rahul for the evening ceremony, sources said.
A big reception will be held in Mumbai on January 23.
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