London (CNN) The head of the British Army will warn that the country's government risks increasing its vulnerability to Russian aggression if it fails to invest further in its military infrastructure.

Gen. Nick Carter is expected to tell the Royal United Services Institute on Monday that Britain will be unable to preempt or respond to adversaries unless its military capabilities are overhauled.

Carter will warn that the UK would struggle to match Russia's military capabilities, citing Russia's long-range missile strikes on Syria, where 26 missiles were deployed from a 1,500 km (930 mile) range.

British Prime Minister Theresa May during a visit to the 1st Battalion The Mercian Regiment in 2016.

He will also highlight Russia's simulated attack exercises across northern Europe, from Kaliningrad to Lithuania, as part of a new tactic in exploiting the gray areas between peace and war.

"Our ability to preempt or respond to threats will be eroded if we don't keep up with our adversaries," Carter is expected to say.

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