We need to make it clear again to Putin that bad behaviour will not pay

Boris Johnson has made a World Cup threat to Russia if Vladimir Putin’s secret services poisoned Sergei Skripal and his daughter.

But in the past we were a lot tougher on Russia.

Back in 1971 another Foreign Secretary, Alec Douglas-Home, expelled 90 soviet diplomats to get rid of espionage on British soil.

Relations were frosty for a time but the message got home that London was not to be trifled with.

Today Russia’s FSB — the modern-day KGB — carry on killing their enemies abroad just as they have always done since the 1920s.

Make no mistake. Putin alone is in charge of Russian security policy.

But the rule is that whenever the FSB makes its hits, nobody should know about his involvement.

When the TV cameras are on him, he simply shrugs his shoulders if asked about any dirty business.

We do not yet know many details about the Skripal poisoning.

But there is a suspicion that he was attacked for betraying secrets to MI6.

He was part of a spy-swap agreed with Moscow.

But if it is shown that the FSB poisoned Skripal, any future spy-swap agreement between Russia and Britain is worthless.

Worthless, that is until London starts to make clear to Moscow that bad behaviour will not pay.

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