Blackberry maker Research In Motion has given in to demands to let Saudi authorities monitor its Messenger service, in a bid stop the kingdom silencing the service.

Sources close to talks between the two parties claim RIM will give Saudi Arabia the unique PIN number and code for each BlackBerry registered in the kingdom, a move that would allow authorities to read encrypted text sent via Messenger.

The arrangement would effectively give Saudi Arabia access to RIM's main server for Messenger, but only for communications to and from Saudi users, the source said.

The Canadian company declined to comment, repeating its earlier statement that is "cooperates with all governments with a consistent standard".