Ukraine and Russia: What you need to know right now

* Russia's defence ministry said on Saturday Ukrainian forces were retreating toward the city of Lysychansk after suffering "critical losses" of up to 90% in some units during fighting for nearby Sievierodonetsk. * Putin said in remarks aired on Saturday that Russian anti-aircraft forces have shot down dozens of Ukrainian weapons and are "cracking them like nuts".

Kyiv was rocked by several explosions early on Sunday, the mayor of the Ukrainian capital said, a day after officials said troops had recaptured a swath of the battlefield city of Sievierodonetsk in a counteroffensive against Russia. FIGHTING * Ukrainian forces have counterattacked in Sievierodonetsk in the east of the country, Britain's defense ministry said. * Luhansk regional Governor Serhiy Gaidai said Ukraine now controls about half of Sievierodonetsk. * Russia's defense ministry said on Saturday that Ukrainian forces were retreating toward the city of Lysychansk after suffering "critical losses" of up to 90% in some units during the fighting for nearby Sievierodonetsk. * Ukraine's state-run nuclear power operator Energoatom said a Russian cruise missile few "critically low" on Sunday morning over a major nuclear power plant. * Russia's defense ministry said on Saturday its forces shot down a Ukrainian military transport plane carrying weapons and munitions near the Black Sea port of Odesa. * Reuters could not independently verify battlefield reports.

WEAPONS AND DIPLOMACY * President Vladimir Putin warned the West that Russia would strike new targets if the United States started supplying Ukraine with longer-range missiles, the TASS news agency reported. * Putin said in remarks aired on Saturday that Russian anti-aircraft forces have shot down dozens of Ukrainian weapons and are "cracking them like nuts". * Spain is to supply Ukraine with anti-aircraft missiles and Leopard battle tanks in a step-up of its military support to the country, according to government sources quoted by El Pais newspaper. * Ukraine rebuked France's President Emmanuel Macron on Saturday for saying it was important not to "humiliate" Russia, a position Ukrainian Foreign Minister Dmitro Kuleba said, "can only humiliate France". ECONOMY * Russian Foreign Minister Sergei Lavrov said on Saturday that Western sanctions would not affect the country's oil exports, predicting a big jump in profits from energy shipments this year.

QUOTE * "The terrible consequences of this war can be stopped at any moment... if one person in Moscow simply gives the order," Ukrainian President Volodymyr Zelenskiy said, an apparent reference to Putin.