The respected defence and security think tank RUSI has warned Theresa May against using the UK's security capabilities as part of her bargaining during Brexit talks.
The UK is a leader in Europe on defence and intelligence matters, with some of the best-funded and -equipped agencies in the EU bloc, making the country a vital partner on defence and security cooperation – a fact said to be one of the UK's trump cards in exit negotiations.
However, a new RUSI report – authored by deputy director Professor Malcolm Chalmers, who has advised the government and parliament on security matters – warns such a tactic could damage vital security relationships.
In strong words for the usually carefully worded body, the RUSI briefing says making defence cooperation conditional on good trading deals could bring serious risks to the NATO alliance at a time of significant global instability.
"It would be seen – both by allies and potential adversaries – as suggesting that the UK’s move towards isolationism was more deep seated than previously feared," the report warns.
"The reassurance value of the UK’s contribution to collective defence rests, to a considerable extent, on its reliability. The government would have to think very carefully before calling this, and therefore its wider commitment to NATO, into question."
The report also cautions against making security commitments conditional, as incoming US president Donald Trump has done, warning countries they will need to contribute financially if they are to benefit from the USA's military.
"As with Trump linking US security guarantees to increased contributions from European and Asian allies during his presidential campaign, such an approach would undermine the mutual confidence on which those guarantees depend," it states.
Separately, the report warns that Brexit is likely to damage the UK's strategic interests on security owing to a reduction in the country's diplomatic clout.
"It will be hard for the UK to maintain its influence in areas (such as the Balkans, Ukraine, North Africa and Turkey) where access to EU markets and, in some cases, the prospect of EU membership, is a powerful policy lever, and where other EU member states are likely to take advantage of Brexit to increase their own influence," it says.
"UK influence on European security will remain considerable, given its position as NATO’s most capable, and willing, European power. Yet it will become harder for the UK to translate this commitment into political influence."
James Ball is a special correspondent for BuzzFeed News and is based in London. PGP: here
Contact James Ball at James.Ball@buzzfeed.com.
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