Robert Vadra,  the brother-in-law of Congress president Rahul Gandhi, was Friday questioned by the ED for about seven hours in connection with a money laundering case related to the purchase of alleged illegal assets abroad, officials said.

They said the businessman was grilled the entire day after he appeared before the Investigating Officer (IO) of the case at the agency's office at Jamnagar House in central Delhi.

Vadra has been questioned in this case multiple times in the past. He has also deposed before the agency in Jaipur where a separate money laundering case is being investigated by the Enforcement Directorate (ED).

The officials said the agency is confronting Vadra in Delhi with documents and statements of other accused being investigated in the case and his statement is being recorded under Section 50 (powers of authorities regarding summons, production of documents and to give evidence) of the Prevention of Money Laundering Act (PMLA).

A Delhi court, on February 16, had extended his interim bail till March 19 in the money laundering case being probed in Delhi.

The agency had told the court that day that he was not cooperating in the matter and it needed to question him further. The court had then directed Vadra to cooperate in the investigation.

Vadra's appearance before the ED is related to a criminal complaint on allegations of money laundering to purchase assets abroad in an alleged illegal manner.

His legal team has denied the charge and said he was ready to come for questioning as and when called.

The ED case against Vadra relates to allegations of money laundering in the purchase of a London-based property, located at 12, Bryanston Square and worth 1.9 million pounds, which is allegedly owned by the businessman in a "benami" way.

The agency had told the court that it had received information about various new properties in London that belonged to Vadra. These include two houses -- one worth 5 million pounds and the other valued at 4 million pounds -- six flats and other assets.

Vadra has denied the allegation of possessing illegal foreign assets and termed it a political witch-hunt against him. He has said he is being "hounded and harassed" to subserve political ends.

His first appearance before the ED last month had acquired political overtones after Priyanka Gandhi Vadra, his wife and Congress general secretary in-charge of eastern Uttar Pradesh, had accompanied him to the investigating agency's office and picked him up after questioning another time.

Vadra had also deposed before the ED twice in Jaipur in connection with another money-laundering case related to an alleged land scam in Bikaner.