"Nord Stream AG has started mobilization of all necessary resources for a survey campaign to assess the damages in cooperation exchange with relevant local authorities. Currently, it is not possible to estimate a timeframe for restoring the gas transport infrastructure," the company said in a statement.
The operator further indicated that the pressure drop on both strings of Nord Stream prompted officials to confidently assume the leakage is caused by physical damage that occurred within the exclusive economic zone (EEZ) of Denmark and Sweden, respectively.
"The positions of two assumed damages have been identified and are located north-east from Bornholm in Swedish and Danish EEZ, respectively," the operator added.
Nord Stream AG has stated that it immediately informed the relevant coast guard authorities about the incident, adding that the causes of the incident will be established as a result of an official investigation into the matter.
The revelation of the leak comes amid German media reports that the US' Central Intelligence Agency warned Germany over the summer about possible attacks on the Nord Stream 1 and 2 gas pipelines.
A German government spokesperson declined to comment on the activities of foreign intelligence agencies.
Nord Stream 1 was delivering natural gas to Germany from Russia before Gazprom halted it in August, while Nord Stream 2 was never turned on; however, both were filled with gas.