|HMS Queen Elizabeth is one of two new aircraft carriers for the Royal Navy|
Russia and China have gained the surveillance and precision strike capabilities to put western ships, large military aircraft and even any land system at "serious risk" - even the most heavily armoured.
The warning comes in a report by the Royal United Services Institute (RUSI), which calls for the Ministry of Defence to place a higher priority on protecting the country against these threats.
The report said: "The UK's potential adversaries have also focused on developing relatively inexpensive weapons that can disable or destroy expensive assets.
"Missiles costing (much) less than half a million pounds a unit could at least disable a British aircraft carrier that costs more than £3bn.
"Indeed, a salvo of 10 such missiles would cost less than $5m.
"China and Russia appear to have focused many (but not all) their efforts on being able to put at risk the key Western assets that are large, few in number and expensive."
|The HMS Queen Elizabeth before its maiden voyage last month|
Defence Secretary Sir Michael Fallon had described Moscow's only aircraft carrier, the Admiral Kuznetsov, as "old and dilapidated", adding that Russia would be looking at Britain's new vessel with a "little bit of envy".
But Russian spokesman Igor Konashenkov had dismissed the British aircraft carrier as "just a convenient oversized target at sea", saying: "It is in the interests of the British Royal Navy not to show off the 'beauty' of its aircraft carrier on the high seas any closer than a few hundred miles to its Russian 'distant relative'."
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China destroyed a satellite as a test 10 years ago and, since then, there have been reports that Russia is trying to develop the same capability, including an airborne laser system.
"Space assets are vulnerable to electromagnetic and physical attack that could - for example - destroy or degrade navigation and communication systems," the report said.
A spokesman for the Ministry of Defence said: "We keep all threats under constant review and we are confident our new aircraft carrier, and other state-of-the-art equipment, is well protected thanks to defensive systems we have invested in as part of our £178bn equipment plan."