The Centre has sought explanations from WhatsApp, Telegram and Signal over their username feature, with IT Secretary S Krishnan on Friday warning that it poses a "serious" risk of impersonation and cybercrime. The government has asked the platforms to justify the feature, which allows users to communicate without sharing their phone numbers.

The government's concerns come days after Meta-owned WhatsApp announced plans to roll out the username feature in India. The Centre subsequently served a notice asking why action should not be initiated under the IT Act and related rules. It also sought detailed information from the company and directed WhatsApp to pause the feature until all consultations are completed "to the satisfaction of the government".

Telegram and Signal, which already offer the username feature, have also received similar notices. While WhatsApp has around 50 crore users in India, Telegram's user base is significantly smaller.

Addressing reporters on the sidelines of a CII Cybersecurity Summit, IT Secretary S Krishnan said the government views the feature as a potential enabler of online fraud and identity misuse.

"We have taken up the issue of usernames because there is a serious possibility of impersonation and the kind of encouragement or facility it provides for committing more cybercrimes. It is a very serious issue," Krishnan said.

He noted that the Supreme Court, while hearing a case related to digital arrest scams, has also been examining cybercrime-related issues. According to Krishnan, the username feature introduces "another dimension" to the ways cybercriminals can exploit digital platforms.

"...which is the reason why we have directed WhatsApp to explain why they have this feature and likewise similarly we have sought explanation from others," Krishnan added.