Shortages of grain and fertiliser could cause ‘mass hunger and famine, says chief, as World Bank pledges another $12bn to ease shortfall

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The United Nations has warned that the war in Ukraine has helped to stoke a global food crisis that could last years if it goes unchecked, as the World Bank announced an additional $12bn in funding to mitigate its “devastating effects”.

UN secretary general António Guterres said shortages of grain and fertiliser caused by the war, warming temperatures and pandemic-driven supply problems threaten to “tip tens of millions of people over the edge into food insecurity”, as financial markets saw share prices fall heavily again on fears of inflation and a worldwide recession.

Ukraine’s president, Volodymyr Zelenskiy, used his nightly address to claim that Russia’s use of laser weapons to down drones to save stocks of conventional missiles “indicates the complete failure of the invasion” and that mistakes had been made at the highest level. He compared their use to propaganda efforts by Nazi Germany promoting a “wunderwaffe” or “wonder weapon”. Russia has claimed it is using a new generation of laser weapons to burn up drones.

Zelenskiy said he had signed a decree to extend martial law by 90 days in order to allow further time to expel invasion forces. The decree needs to be approved by parliament.

Sweden and Finland have formally submitted their applications to join Nato but Turkey blocked an early move to fast-track the Nordic countries’ requests, demanding they extradite “terrorists” and that the alliance respect its concerns. US president Joe Biden said Washington would in the meantime work with Finland and Sweden in the event of the “threat of aggression”.

The US embassy in Kyiv has resumed operations, the US secretary of state, Antony Blinken, said after nearly three months of closure. A small number of diplomats will return initially to staff the embassy, according to a spokesperson.

G7 finance minister will meet in Brussels on Thursday hoping to find a solution for Kyiv’s budget troubles as the fallout from Russia’s invasion of Ukraine continues to roil the global economy. The US has already pledged a $40bn aid package to fill Kyiv’s coffers and military stores.