Government sources said more information has been sought based on the replies received.
While they did not give the names of the countries that have responded to the Letters Rogatory (LR), as the details will be given to the Supreme Court, sources said they are hopeful of getting more substantial information.
The Supreme Court has asked both Central Bureau of Investigation and the Enforcement Directorate to submit status reports on their probe to it by February 10, when the 2G spectrum case will come up for hearing.
The Enforcement Directorate had late last year send out LRs to 10 countries including Russia, UAE, Isle of Man, Cyprus, Mauritius, Norway, Singapore and Libya.
A Letter Rogatory is a formal request issued by a competent court to a foreign court and processed by the ministry of external affairs on behalf of the investigative agencies to obtain information about individuals and entities.
Even prior to sending of the LRs, the ED, which is jointly probing the multi-crore-rupee scam with the CBI, had already approached their counterparts in overseas countries having footprints of some telecom companies allotted the spectrum between September 2007 to January 2008 on a semi-formal basis.
Sources said ED feels that some entities operating in those countries were connected with the spectrum allocation besides certain others who later bought stakes in Indian companies that had bagged the spectrum.
Most of the companies that had bagged the spectrum had their subsidiaries and business partners situated in foreign countries. Untangling the financial transactions web spread across various countries is what the ED is focusing on.
Sources said the Directorate has also finished with the second round of questioning of certain telecom firms.
Both ED and CBI are working in close cooperation with the case. The CBI had even roped in the Directorate in multi-city raids carried out late last year in connection with the probe.
A source said while the CBI is looking at the possible criminal conspiracy angle in allocation of spectrum, ED is focusing on the money trail.