"I'm truly so happy for my friend Bipasha Basu and her handsome bridegroom to be Karan Singh Grover. You are a golden heart...You deserve so much and more," Priyanka tweeted.
There are speculations that they will have a Bengali wedding at Bipasha's residence followed by an elaborate reception at night.
While Priyanka and Bipasha, 37, have shared screen space in 2005 film 'Barsaat', the 'Quantico' actress hosted the third season of celebrity stunt-based show 'Khatron Ke Khiladi' where Karan was a participant.
Bipasha and Karan, 34, began dating after starring in 2015 horror film 'Alone'. This is the 'Jism' star's first marriage and the 'Hate Story 3' actor's third.
Karan was first married to TV actress Shraddha Nigam and then to Jennifer Winget.