Britain's senior-most military officer is warning that an improving Russian navy poses risks to undersea communications and Internet cables, saying any disruption could do "catastrophic" damage to the economy.

Air Chief Marshal Sir Stuart Peach said Britain and NATO need to prioritize protecting communications cables running along the seabed between countries and continents to prevent them being severed.

Speaking to the Royal United Services Institute, Peach said the vulnerability posed "a new risk to our way of life."

"Can you imagine a scenario where those cables are cut or disrupted, which would immediately and potentially catastrophically affect both our economy and other ways of living if they were disrupted," Peach said.

"Therefore we must continue to develop our maritime forces with our allies, with whom we are working very closely, to match and understand Russian fleet modernization," which he said included "new ships and submarines" and efforts "to perfect both unconventional capabilities and information warfare."

According to a recent report by the think tank Policy Exchange, such deep-sea cables "carry 97 per cent of global communications and $10 [trillion] in daily financial transactions," The Financial Times reports.

Copyright 2017 NPR. To see more, visit