Bhupinder Singh Hooda said that the BJP government is pursuing "vendetta politics".
The Gurgaon police have sought permission from the state government to probe the case registered against former Haryana chief minister Bhupinder Singh Hooda over a land deal which allegedly favoured Congress leader Sonia Gandhi's son-in-law Robert Vadra.
Bhupinder Singh Hooda and Robert Vadra were booked by police on Saturday in connection with alleged irregularities in the deal.
The BJP had made the deal a major issue in the the 2014 election, alleging that Robert Vadra made crores of rupees with the connivance of the then Hooda-led Congress government.
Under the amended Prevention of Corruption Act, the police have to get approval of the 'competent authority' before investigating an FIR against a public servant, a senior official said Tuesday.
The Gurgaon police wrote to the state government on September 1 for this permission to investigate Bhupinder Singh Hooda, Gurgaon Police Commissioner K K Rao said Tuesday.
He said once the permission is given the investigation will start.
The FIR against Robert Vadra, Bhupinder Singh Hooda and two companies -- DLF and Onkareshwar Properties -- was registered at Kherki Daula police station in Gurgaon.
The accused were booked under Sections 420 (cheating), 120 B (criminal conspiracy), 467 (forgery), 468 (forgery for the purpose of cheating), 471 (using as genuine a forged document) of the IPC and Section 13 of the Prevention of Corruption Act.
Bhupinder Singh Hooda said on Tuesday in Jaipur that the BJP government is pursuing "vendetta politics".
The Congress leader claimed the case has been lodged to divert attention from the Rafale fighter aircraft deal.
Haryana Chief Minister Manohar Lal Khattar, however, said the BJP government is committed to uprooting corruption.
"The FIR registered on Saturday will be thoroughly examined and investigated," Mr Khattar had told reporters in Gurgaon on Sunday.
The FIR was lodged after a complaint was received from one Surinder Sharma, a resident of Nuh.
It said Robert Vadra's Skylight Hospitality Pvt Ltd purchased 3.5 acre of land in Gurgaon's sector 83 from Onkareshwar Properties for Rs 7.50 crore in 2008, when Bhupinder Singh Hooda was the chief minister and also held the portfolio of Town and Country Planning Department.
Later, Skylight Hospitality sold this land to realty major DLF for Rs 58 crore after procuring commercial licence for the development of the colony with the influence of Hooda, Sharma alleged.
In turn, DLF was favoured by the Bhupinder Singh Hooda government with permission to develop another piece of land, it was alleged.
The Khattar-led BJP government set up a one-man commission headed by Justice (retd) S N Dhingra in 2015 to probe the grant of licences for developing commercial colonies in Gurgaon's sector 83.