Putin’s attack on the grain deal was despicable. It also shows he’s desperate | Hamish de Bretton-Gordon

For the deal to work and global food supplies to get moving again, Ukraine's ports and ships need Nato protection

Over the weekend, Russia signed a deal with Ukraine to allow grain exports to resume from three Ukrainian ports, thereby easing the global food crisis. Before the ink was dry, Russian forces fired precision missiles into the port of Odesa as grain was being readied for export.

This is clearly the behaviour of a tyrannical despot, one whose word cannot be trusted. But it may also be an act of desperation: Richard Moore, the head of MI6, told a US security conference last week that the Russian army is about to run out of steam".

Hamish de Bretton-Gordon is a chemical and biological weapons expert and a fellow at Magdalene College, Cambridge