Ukraine and Russia: What you need to know right now

* Donetsk regional governor Pavlo Kyrylenko told Ukrainian television there was constant shelling along the front line, with Russia attempting to push towards Sloviansk and Kramatorsk, the two biggest Ukrainian-held cities in Donetsk. * Britain's defence ministry said on Twitter that Russia's broader plan likely continues to be to cut off the Sievierodonetsk area from both the north and the south.

Ukrainian troops battled Russians street-to-street in the ruins of Sievierodonetsk, trying to hold onto gains from a surprise counter-offensive that had reversed momentum in one of the bloodiest land battles of the war. FIGHTING

* Ukrainian defenders are doing everything possible to hold their position in the frontline eastern city of Sievierodonetsk even as Russia sends more troops to the area, mayor Oleksandr Stryuk told Ukrainian television. * Donetsk regional governor Pavlo Kyrylenko told Ukrainian television there was constant shelling along the front line, with Russia attempting to push towards Sloviansk and Kramatorsk, the two biggest Ukrainian-held cities in Donetsk.

* Britain's defence ministry said on Twitter that Russia's broader plan likely continues to be to cut off the Sievierodonetsk area from both the north and the south. * The bodies of Ukrainian fighters killed defending the city of Mariupol from Russian forces at a vast steel works have been handed over to Kyiv, the families of Ukraine's Azov unit of the national guard said.

* Russia's Defence Minister Sergei Shoigu said Ukrainian ports of Mariupol and Berdyansk, seized by Russian forces, had been de-mined and were ready to resume grain shipments. He said 6,489 Ukrainian military personnel had so far surrendered. * Russia has prosecuted around a dozen army officers after hundreds of conscripts were wrongly sent to fight in Ukraine, a military prosecutor said.

DIPLOMACY AND WEAPONS * Ukrainian President Volodymyr Zelenskiy said his country had already lost too many people to simply cede any territory.

* Zelenskiy must not be pressured by world powers into accepting a bad peace deal with Russia, British Prime Minister Boris Johnson told his ministers. * Russia imposed sanctions on 61 U.S. officials including U.S. Treasury Secretary Janet Yellen and Energy Secretary Jennifer Granholm, in retaliation for "constantly expanding U.S. sanctions", the foreign ministry said.

ECONOMY * Ukraine could export a maximum of only 2 million tonnes of grains a month if Russia refuses to lift its blockade of the country's Black Sea ports, said Taras Vysotskyi, Ukraine's first deputy minister of Agrarian Policy and Food.

* Turkey is coordinating closely with Russia and Ukraine to agree a plan that would re-start grain exports from Ukrainian ports, Defence Minister Hulusi Akar said. QUOTE

"I do not even know where to start. I am standing here looking but I have no idea what to do. I start crying, I calm down, then I cry again," said Nadezhda, a resident of Druzhkivka in the Ukrainian-held pocket of Donetsk province, surveying the ruins of her shelled home.