Three of Britain's four Vanguard-class nuclear submarines are at sea at once in a deployment unseen for over five years, with sources citing readiness, not a signal to Russia

Three of Britain's four Vanguard-class nuclear submarines are simultaneously at sea in an unusual deployment not seen for more than five years, The Times reports.

At least one submarine is carrying Trident ballistic missiles armed with nuclear warheads. The other two are believed to be conducting sea trials or preparing for operations. HMS Victorious, the fourth submarine, is undergoing maintenance in Devonport.

Naval sources described the deployment as unusual but suggested it reflects improvements in the Royal Navy's operational readiness, rather than a deliberate signal to Russia.