Special Judge Arvind Kumar directed him to join the ED investigation on the evening of February 6.

The court was hearing Vadra's anticipatory bail plea.

The case relates to ownership of undisclosed assets abroad worth 1.9 million pounds allegedly belonging to Vadra, the brother-in-law of Congress President Rahul Gandhi.

The ED lodged a money laundering case against Vadra's close aide Manoj Arora after his role surfaced during the probe of another case by the Income Tax Department under the new Black Money Act and tax law against absconding arms dealer Sanjay Bhandari.

It said the London-based property was bought by Bhandari and sold in 2010 for the same amount despite incurring additional expenses on its renovation.

On December 7, as part of its investigation, the ED conducted searches at a number of premises in Delhi-NCR and Bengaluru.