LONDON -- British Defense Secretary John Healey said Thursday that Britain and Norway tracked three Russian submarines in North Atlantic.

In a 10 Downing Street press conference, he said that British forces, together with allies including Norway, had led a month-long operation in the North Atlantic to track Russian submarines near key undersea infrastructure, including cables and pipelines.

He added that the vessels had since left British waters and headed north, with no signs of damage found to underwater infrastructure.

According to Healey, the operation involved a British frigate, aircraft and hundreds of personnel. He said the Russian deployment included one Akula-class attack submarine and two specialist submarines linked to Russia's Main Directorate for Deep Sea Research, known as GUGI.

So far, there has been no response from the Russian side to Healey's statement.