Climate change is opening new shipping lanes that will allow chinese warships a quicker route into atlantic waters, the head of the royal navy has warned, as he set out emerging threats to british maritime security.

Tony radakin, the first sea lord, told an audience on the prince of wales aircraft carrier in portsmouth that melting ice in the high north was freeing the passage of ships through the arctic, to the advantage of both china and russia.

Climate change is a concern for all of us, but it is opening up new maritime trade routes across the top of the world, halving the transit time between europe and asia, adm radakin said on thursday.

When china sails its growing navy into the atlantic, which way will it come the long route, or the short? and these routes skirt the coast of resurgent russia. a russia that is now more active in the atlantic...than it has been for over 30 years.

The northern sea route which runs along the north coast of russia and the nordic nations is currently only passable between august and october, but may be more accessible if global temperatures continue to rise.

The royal navy has only one vessel, hms protector, which can operate in high polar regions. britain is already working with the us, norway and canada on joint exercises to secure the arctic region from hostile activity, but senior naval officers are keen to make the case for more ships with ice-breaking hulls ahead of this autumns integrated defence and security review.

Western allies have been more aware of the threat posed by the chinese navy after a pentagon report revealed in september that beijing had bypassed washington to amass the worlds largest naval fleet, with 350 ships and submarines. mark esper, us defence secretary, announced plans this week to expand the us navy with a range of unmanned and autonomous ships as well as a more potent attack submarine force to match chinas capability.

However, adm radakin also warned of threats closer to home, pointing out that sensitive undersea cables carrying 97 per cent of the worlds internet data were at risk from interference by moscow. our adversaries are already threatening these [cables], the first sea lord said. this is why the government is committed to developing new capabilities to protect those cables, standing up to this threat on behalf of everyone.

Rishi sunak, uk chancellor, described an attack on britains undersea cable network as an existential threat to [british] security in a paper published three years ago by the policy exchange think-tank. the paper, which was written before mr sunak became chancellor, highlighted russias record in disrupting communications infrastructure, as it did during the annexation of crimea.

The exact locations of these cables are both isolated and publicly available jugulars of the world economy which are a singularly attractive target for our enemies, mr sunak wrote.