'News about my marriage is true. We have been separated for over a year and divorce talks are on. I request all to respect my family's privacy,' she wrote on Twitter.
According to a report in the Deccan Chronicle, the couple had filed a petition for divorce in the family court.
Soundarya got married to Ashwin in 2010. Click here to see the photographs from their wedding.
Their son Ved is a year old.
As per reports, the reason for the split is irreconcilable differences between the couple.
Papa Rajinikanth apparently stayed with the couple after returning from the US, where he had been undergoing treatment for a kidney-related ailment, and hoped to effect a reconciliation. Unfortunately, it did not work out.