The Enforcement Directorate has registered a money laundering case against former Union minister Dayanidhi Maran and his brother Kalanithi, in connection with the 2G spectrum allocation case.

The case, registered on Tuesday under the Prevention of Money Laundering Act (PMLA), pertains to an alleged illegal gratification of about Rs 550 crore allegedly received by the Maran brothers in the Aircel-Maxis deal.

Maran had quit the Cabinet last year after allegations that he had favoured Malaysian firm Maxis over Aircel in grant of telecom licences in 2004-05. Maran had denied the allegations.

The Central Bureau of Investigation, too, is probing Maran and Sun TV managing director Kalanithi in connection with these allegations. The agency is also investigating alleged contraventions of foreign exchange rules in this deal, as it registered an enforcement case information report.

The agency has also registered another charge in the 2G case, pertaining to the National Democratic Alliance regime and has named former telecom secretary Shyamal Ghosh, then deputy director general J R Gupta and a few telecom companies for alleged irregularities in the grant of additional 2G spectrum during 2001-03.