Russia-Ukraine war: what we know on day 51 of the invasion | Ukraine

The Russian flagship cruiser Moskva has sunk in the Black Sea off southern Ukraine, according to Russia’s defence ministry. It is still unclear whether the ship was hit by Ukrainian weaponry. Ukraine claims it was, but Russia maintains that a fire on board and then “stormy sea conditions” while it was being towed to port were to blame. Russia only has three of this flagship class of warship, which have crews of almost 500 sailors, and the loss of the Moskva is a big blow. The former CIA director David Petraeus described Russia’s admission as a “rare moment of truth … I’m surprised that they admitted it,” he told the BBC.

Vladimir Putin may resort to using a tactical or low-yield nuclear weapon in light of military setbacks in the invasion of Ukraine, the CIA director, William Burns, has said. During a speech in Atlanta, Burns said: “Given the potential desperation of President Putin and the Russian leadership … none of us can take lightly the threat posed by a potential resort to tactical nuclear weapons or low-yield nuclear weapons.” The Kremlin placed Russian nuclear forces on high alert shortly after the assault began on 24 February.

Russia has asked Brazil for support in the International Monetary Fund, the World Bank and the G20 group of top economies to help it counter crippling sanctions, according to a letter seen by Reuters. On 30 March the Russian finance minister Anton Siluanov wrote asking for Brazil’s “support to prevent political accusations and discrimination attempts in international financial institutions and multilateral fora”. A Brazilian economy minister spokesperson indicated that Brazil would like Russia to remain part of discussions at multilateral organisations.

The lives of about 2.7 million people with disabilities are at risk in Ukraine, a UN committee has warned, citing reports that many are trapped or abandoned in their homes, care centres and orphanages without basic supplies or medicines. The committee said it was “deeply disturbed” that the fate of people with disabilities in Ukraine is “largely unknown”.

At least 503 civilians, including 24 children, have been killed in Ukraine’s eastern Kharkiv region since Russia launched its invasion on 24 February, the region’s local governor has said. Kharkiv, Ukraine’s second city with a prewar population of about 1.5 million, is 40km (25 miles) from the Russian border.

Russia’s deputy foreign minister Alexander Grushko said Moscow would take “security and defence measures that we will deem necessary” if Sweden and Finland join Nato. In an interview with the Russian state-owned news agency Tass, the minister said the membership in the military alliance would “seriously worsen the military situation” and lead to “the most undesirable consequences”. Finland and Sweden had earlier taken a major step towards joining Nato.

Russia’s investigative committee said Ukrainian forces carried out at least six helicopter airstrikes on the village of Klimovo in the Russian region of Bryansk, injuring seven people. The Bryansk region governor said earlier that two residential buildings in the village had been…