Expensive military assets like Britain's new aircraft carriers are increasingly vulnerable to new, cheaply-produced precision missiles being developed by Russia and China, a military think tank has warned.
A report by the Royal United Services Institute said the advancing capabilities of potential adversaries should be a matter of "genuine concern" for the Ministry of Defence (MoD).
Developing technology to protect its warships and other large assets had not been a priority for the MoD, the report said and it called for a greater emphasis on "protective capabilities" in future.
It said that Russia and China had acquired the surveillance and precision strike capabilities to put at "serious risk" Western surface ships, large military aircraft and arguably any land system, "even the most heavily armoured".
"The UK's potential adversaries have also focused on developing relatively inexpensive weapons that can disable or destroy expensive assets," it said.
"Missiles costing (much) less than half a million pounds a unit could at least disable a British aircraft carrier that costs more than £3 billion. Indeed, a salvo of 10 such missiles would cost less than five million dollars.
"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 report said that potential adversaries of Britain, the US and their allies were also looking at ways to disrupt the West through the development of cyber and anti-satellite capabilities.
"Cyber is particularly appealing to the West's rivals since the development of significant capabilities does not require a large capital investment or the wide-ranging knowledge base needed, for instance, for the development of a new combat aircraft," it said.
However, it said the UK also made extensive military use of space for surveillance, communication, intelligence and navigation, including the control of missiles flying within the atmosphere, creating further vulnerabilities.
The Chinese carried out the test destruction of a satellite in 2007 and since then, there have been numerous reports of Russia seeking to acquire anti-satellite capabilities, 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.
The report's co-author Professor Trevor Taylor said: "UK defence policy prioritises the capability to project force to areas of concern and to deter attacks on British assets and allies.
"The advancing capabilities of potential adversaries in Northern Europe, the Middle East and even East Asia need to be taken into account in reviews of UK defence policy and military tasks, British and Nato approaches to deterrence strategy, and the priorities for UK capability development."
A MoD spokesman 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 £178 billion equipment plan."