The city of Kyiv may have been safe enough for Boris Johnson to visit at the weekend, but it would be unwise for anyone to conclude that Vladimir Putin is close to being beaten. Russia has been humiliated in the north of the country, with its war crimes in once-occupied towns such as Bucha exposed. But the Kremlin’s strategy still appears to be to reconstitute its forces, including with discharged army personnel, and to redeploy them to take part in the offensive in the south.

This new phase of the conflict presents new dangers for the Ukrainians. Thus far, they have excelled against the clunking fist of the Russian war machine by embracing flexible tactics, making the most of their defensive advantage, and exploiting Russia’s logistical difficulties. But if the Russians are to be dislodged from the territory they occupy in southern Ukraine, it will require more than anti-tank missiles from the West. A few countries are donating Soviet-era tanks, while the UK will deliver anti-ship missiles and armoured vehicles. This is unlikely to be enough.

The scenario that must be avoided is the Russians seizing Mariupol and then launching an assault towards the port city of Odesa. If successful, it would result in Ukraine being cut off from the Black Sea, crippling its ability to trade internationally. It could also leave Putin in an undeserved position of strength in any future peace negotiations given that he would have occupied a coherent swathe of Ukraine’s territory.

The West is understandably wary of doing anything that could provoke a direct confrontation between Nato and Russia. However, it must also not be intimidated by Putin’s threats. His army’s failures have humbled him. But he has not been defeated yet.