Sources close to the actor said they will have a civil marriage either at his home in suburban Bandra or at his parents' residence to be attended by close family members.
The couple will head to Panchgani, a hill station in Western Maharashtra, for a reception at a hotel on December 29, which will be attended by their families and prominent film personalities.
Preparations for the reception have been kept a closely guarded secret, the sources said.
This will be the second marriage for the 40-year-old Khan, who divorced his first wife Reena three years ago. Kiran is an assistant director to filmmaker to Ashutosh Gowarikar. The two met for the first time during the making of 2001 Oscar nominated 'Lagaan', which was produced by Aamir, who had also acted in the critically acclaimed and commercially hit film.
Aamir, who made his Bollywood debut with superhit 'Qamayat Ke Qayamat Tak' in late 1980s, was seen in only one film this year 'Mangal Pandey' directed by Ketan Mehta.
Next year will see him as a 20-something hero in 'Rang De Basanti'.
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