The ultimatum was issued hours after senior officials from government, intelligence and state-run telecom operators met to discuss how to gain access to the content, the latest global headache for Research In Motion (RIM).

The Indian government said in a statement that if its demands were not met phone operators would be required by law to close the rock-solid encrypted BlackBerry Enterprise email and Messenger services running through their networks.

"If a technical solution is not provided by 31st August, 2010, the Government will review the position and take steps to block these two services from the network," the government said.

Shares in RIM traded down C$2.06 at C$56.72 in a Toronto market that was down 0.4 percent by 1349 GMT. The Waterloo, Ontario-based company has declined to comment on the talks.