India’s realty major DLF Ltd’s shares fell sharply Monday after the anti-corruption activists led by Arvind Kejriwal accused the company of having clandestine dealings with Robert Vadra, Congress (I) president Sonia Gandhi's son-in-law.

The shares of DLF, India’s biggest property developer fell by 7.48 percent to Rs. 223.80 Monday on the Bombay Stock Exchange’s Sensex. Anti-corruption activist Kejriwal and members of his newly formed political party India Against Corruption (IAC) Friday accused DLF of favoring Vadra by arranging for him favorable real estate transactions and funds, an allegation which both the DLF and Vadra have denied.

“We would like to state that the business relationship of DLF with Robert Vadra or his companies has been in his capacity as an individual entrepreneur, on a completely transparent and at an arm's length basis. Our business relationship has been conducted to the highest standards of ethics and transparency, as has been our business practices, all around,” DLF said in a statement Saturday.

"The allegations raised against DLF are therefore completely baseless and untrue. ... We have never received any undue benefit from any state government or any government authorities in any part of India,” the statement said.

Vadra, a businessman and married to Sonia Gandhi’s daughter, Priyanka Gandhi, also issued a public statement calling the activists' accusations "utterly false, entirely baseless and defamatory." He said that his business transactions were transparent and were fully reflected in financial statements. 

However, Kejriwal reiterated his allegations against Vadra and tweeted Monday that he planned to reveal more on businessman Vadra at a press conference in New Delhi at 5 p.m. Tuesday, DNA reported.

"DLF granted favors to Shri Robert Vadra. What favors did Haryana government grant DLF? How is DLF reply a bunch of lies? Will speak tomo at 5pm," his tweet read.

Married to the powerful first family of India, Vadra initially chose to respond to the allegation through social networking site Facebook. However, he chose to close his Facebook account Monday.

Finance Minister P. Chidambaram, when questioned about the scandal, said that the allegations against Vadra and DLF were about private transactions which the government could not probe.

"...unless there is a specific allegation of quid pro quo or corruption, I am afraid private transactions cannot and ought not to be allowed to be questioned on the basis of imputations and insinuations," Chidambaram said to the reporters on the sidelines of the Economic Editors' Conference in New Delhi, DNA reported.

Sonia Gandhi is the president of the ruling Congress party. Though she doesn’t hold any government portfolio, she is one of the most powerful political figures in the country and influences the government on policy issues.