He was presented before Special Judge Arvind Kumar who allowed the ED to quiz him for another five days.
Khaitan was arrested on Friday, a week after the Income Tax Department raided hiss offices and various other properties in Delhi and the National Capital Region (NCR).
The ED told the court that they have found evidence of different entries in his various accounts and that needed probing.
Khaitan’s counsel Pramod Kumar Dubey opposed the ED plea saying, the arrest was illegal.
The ED said the lawyer had been “controlling” the modus operandi and was responsible for routing the money, misusing his connections and clients, including the ones inherited from his father, to launder the money through a variety of accounts in Dubai, Mauritius, Singapore, Tunisia, Switzerland, the UK and India.
Agency officials said the accounts included those of his undisclosed shell companies outside India.
Earlier, Khaitan was arrested in September 2014 for his alleged involvement in the AgustaWestland deal.
He got bail in January 2015 and was again arrested along with Sanjeev Tyagi, another accused in the case, on December 9, 2016, by the CBI. He later secured bail.
The CBI chargesheet has described Khaitan as the brain behind the AgustaWestland deal.