In mid-September it seemed that Vladimir Putin might be looking for a way out of the war in Ukraine. On the 15th of that month, Putin made an almost apologetic statement during his meeting with China’s President Xi Xinping in Samarkand.

Putin was quoted as saying: “We understand your questions and concern about this.” Xi replied: “China is willing to work with Russia to play a leading role in demonstrating the responsibility of major powers, and to instil stability and positive energy into a world in turmoil.” This looked like a carefully scripted (by the Chinese) exchange designed to show that China wants Putin to bring the conflict to an end. Given how Putin’s actions have complicated Xi’s own ambitions towards Taiwan, this is hardly surprising.

And yet, everything Putin has done since that meeting in Uzbekistan would suggest quite the opposite; that he is doubling down on the disastrous war. Particularly, since Ukraine’s attack on the Kerch bridge on 8th October, there has been a deliberate attempt to inflict serious damage on Ukraine’s power infrastructure, initially using Russia’s dwindling stocks of missiles and later Iranian Shahed-136 drones which were reportedly acquired in mid September.

Behind this change of strategy stands the grim and brutal figure of Russia’s new military commander, General Sergei Surovikin, who is credited with saying “I don’t want to sacrifice Russian soldiers’ lives in a guerrilla war against hordes of fanatics armed by NATO…..We have enough technical means to force Ukraine to surrender.”

In fact the two themes; a wish to end the war and the intensification of conflict; are not necessarily contradictory. Both sides know that winter is coming soon and that the front lines are likely to be frozen until early Spring 2023. So, there is a desire by both sides to achieve the best position possible before fighting becomes increasingly difficult. However Putin must know that, prior to any ceasefire or peace negotiation, he must drastically reduce Ukraine’s morale and ambition which have been so fortified by the victories around Kharkiv and the gradual progress towards Kherson.

This change of policy also suggests three additional elements in Kremlin thinking.

Firstly the original objective, back in February, of annexing all or most of the country has finally been abandoned. Russia would ideally have liked to take over a functioning state which needed as little repair as possible. The wholesale destruction of Ukraine’s energy and transport infrastructure demonstrates that any such ambitions have been belatedly jettisoned in favour of leaving Ukraine as an enfeebled and debilitated neighbour.

Russian President Vladimir Putin has signalled a change in approach in his war in Ukraine with threats of a 'dirty bomb' now among his strategy.

Secondly, Moscow believes the West will have to pick up the bill for rebuilding Ukraine, much as Washington and Brussels might dream of using frozen Russian assets. Any such funding will be hard to find at a time of strained budgets and the current energy crisis. President Zelensky has recently complained that “zero” of the funds promised by the European Union for the recovery, reconstruction and modernisation of Ukraine have been paid.

And thirdly, Putin cannot afford to give up either Crimea or the Donbas in a future negotiated agreement. To avoid personal humiliation at home he must acquire more territory than Russia controlled on before the invasion. At a minimum he will surely want all of Donetsk and Luhansk oblasts and the land route to Crimea. The Zaporizhzhia nuclear power station will be a significant bargaining chip.

The problem with Moscow’s new approach is that it requires the destruction of Ukrainian determination to continue and eventually win the war. There is no doubt that the recent drone attacks have severely hurt Ukraine, which can look forward to a long hard winter with interrupted power supplies. Ukrainians abroad have been advised not to return home until next Spring. However, there is no sign that Ukrainian morale has been seriously damaged.

This must be where the idea of exploding a “dirty bomb” comes in. Moscow has tried to sell a narrative that Ukraine is considering such a move; even though the story carries no credibility. What could possibly be Ukraine’s motive for contaminating its own territory? However Moscow’s information operations in recent years have shown that a lie can be as effective as the truth. The shooting down of the Malaysian airliner in July 2014 provides just one of several examples of how Moscow has obscured the facts through an active policy of disinformation.

By contrast, Putin does have a motive to explode a “dirty bomb” which would spread radioactive waste over a large area without the need for a nuclear explosion. One or more dirty bombs detonated in the centre of Ukraine (far enough away from Russia and surrounding countries) could inflict significant damage on Ukraine’s huge agricultural sector whilst also requiring local people to be relocated from their homes possibly for years.

Putin’s previous threats to use a nuclear bomb may have been intended to deter the West from providing Ukraine with the arms it needed. Even as a last resort to avert defeat, Putin must know that use of a nuclear weapon could unleash untold consequences. But the West needs urgently to tell Putin that a “dirty bomb” would be regarded in a similar vein. Hopefully Xi Jinping will also remind Putin of their conversation in Samarkand.

Tim Willasey-Wilsey is Visiting Professor of War Studies at King’s College London and a Senior Associate Fellow at RUSI. He was formerly a senior British diplomat.

The West urgently needs to go tougher on Putin's threat of a 'dirty bomb' - Tim Willasey-Wilsey