If the British government was expecting Russia to play nice in the row over the British Council then its illusions have been dispelled today.

The Kremlin has wasted no time in sending in the Federal Security Service (FSB), the successor to the KGB, to pile pressure on the British Council's Russian employees at the disputed offices in St Petersburg and Yekaterinburg.

Staff received the late night knock on the door at their homes from FSB officers eager to "explain the situation". They were summoned again this morning for further interviews, a process designed to intimidate them into leaving an organisation that the Kremlin views as a front for British espionage.

The FSB, in a masterpiece of Orwellian double-speak, declared in a statement that its aim was simply "to safeguard Russian citizens from being used as tools in the Britons' provocative games". Presumably, those working cheerfully at the British Council before it fell under President Vladimir Putin's baleful gaze were now suddenly at risk of being held hostage.

It is hard to underestimate the frightening power of the FSB's "persuasion" in a country where the secret police operate without restriction or oversight. Espionage charges are routinely trumped up against scientists and academic researchers, who must often battle Russia's Kafkaesque bureaucracy for years simply to clear their names.

Stephen Kinnock, the Council's director in St Petersburg, now also knows how it feels to receive unwelcome personal attention from Russia's police after being followed and stopped late at night on his way home. His diplomatic status protects him from the worst, a luxury his 23 Russian colleagues in St Petersburg do not enjoy.

David Miliband, the Foreign Secretary, is understandably outraged by all of this. But the problem for the British government is that it can do very little to prevent it, other than shaming the Russian authorities for their actions.

The British Council is very exposed here. While the office in Yekaterinburg is located within the British Consulate, and presumably safe from entry by Russian police as diplomatic territory, there is little to prevent the FSB from marching into the St Petersburg branch, confiscating all the files and padlocking the doors to keep the staff out.

Such a spectacle will be unnecessary anyway if FSB heavies are simply employed outside the Council's offices to demand the names and addresses of any Russian tempted to visit. Few would brave that level of harassment for the chance to brush up on their Shakespeare or learn about study opportunities at British universities.

Britain also faces an uphill task to convince much of the Russian public that the Kremlin is behaving unreasonably. Foreign Ministry officials have made much of the fact that cultural organisations from other countries, including France and Germany, are complying with Russian law as non-governmental organisations and operate without difficulties.

Why, they argue, should Britain be allowed to flout Russian law and get away with it? Numerous Russian friends have asked me whether a Russian organisation in London would be able to ignore an official demand to close down, as the British Council did.

The government insists that the Council has done nothing wrong and is protected by a 1994 cultural agreement with Russia. It is simply a scapegoat in London's battle with Moscow over Mr Putin's refusal to extradite Andrei Lugovoy to face trial for the murder of Alexander Litvinenko, the dissident former FSB officer.

Russian officials don't even bother to hide the fact that the Council's troubles are linked to the row over Mr Lugovoy. They view it as a continuation of a fight picked by Britain when it expelled four Russian diplomats in July in retaliation for Mr Putin's decision.

As such, Russia is determined to win the fight over the British Council, which it sees as a direct challenge to its authority at home. Britain is equally determined to stand its ground.

The question is: what can Mr Miliband do to safeguard the Council's Russian employees who even now are being grilled by the secret police as enemies of the state? Without them, there will be no British Council offices.

The Kremlin is betting that he can do nothing - and not many in Russia are courageous enough to bet against the Kremlin.

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