The Ra.One star picked the designer to create an outfit for her planned wedding to Saif Ali Khan in early 2012, claims Mumbai Mirror.
"Ritu Kumar has a longstanding relationship with Saif's mum Sharmila Tagore, who has also walked the ramp for her on several occasions," a source told the newspaper.
"Kumar even photographed Sharmila and Mansoor Ali Khan Pataudi for her coffee table on the costumes and textiles of Indian royalty in the '90s, where Sharmila wore the traditional Bhopali farshi paijama and dupatta that she wore on her wedding day in December 1969."
The choice of Delhi-based Kumar has suprised many commentators, who had expected Kapoor to choose her friend, Bollywood costume designer Manish Malhotra.
Kapoor and Khan will reportedly announce an official date for their wedding in the next few weeks.
The couple will be seen together in upcoming spy action thriller Agent Vinod.
