Ukraine said Tuesday that it had pushed Russian forces from the flanks of Bakhmut but conceded that Moscow's forces were pushing deeper inside the embattled town.
The announcement came as European leaders meeting in Iceland agreed to create a "register of damages" to record the wartime harm and destruction wrought by Russia in Ukraine, French President Emmanuel Macron said. It would be an initial step towards prosecution of Russian leaders in the future.
A year after kicking Russia out of the Council of Europe (CoE) over its war in Ukraine, the leaders of the 46-nation pan-continental rights body gathered in Reykjavik with the Ukraine conflict topping the agenda.
In Kyiv, authorities were due to host a Chinese special envoy to discuss Beijing's proposals for ending the conflict.
Deputy Defence Minister Ganna Malyar said Ukraine had wrested back about 20 square kilometres (7.7 square miles) of a Russian pincer movement around Bakhmut, the epicentre of fighting in Russia's invasion.
"At the same time, the enemy is advancing in some measure inside Bakhmut itself and is completely destroying the town with artillery," she added on social media.
The commander of Ukraine's ground forces, Oleksandr Syrskyi, had earlier said he visited forces near Bakhmut to hand out awards to Kyiv's troops fighting in the longest battle of the invasion.
"Wagner's men went into Bakhmut like rats into a mousetrap," he said, referring to the Russian paramilitary group.
The British defence ministry said that "over the last four days, Ukrainian forces have made tactical progress, stabilising the flanks of Bakhmut to their advantage".
- 'Unbelievable success' -
The wave of Russian strikes overnight came just over a week after Kyiv announced it had shot down a Kinzhal nuclear-capable hypersonic missile for the first time, using US-supplied Patriot systems.
Russia denied Kyiv's latest claim, to have shot down six of the hypersonic missiles during an overnight barrage.
Ukraine's mounting success in taking out dozens of Russian drones and missiles illustrates its bolstered air defences, after a winter in which Moscow's pummelled key infrastructure.
"Another unbelievable success for the Ukrainian air forces!" Defence Minister Oleksiy Reznikov said on Twitter.
The defence ministry said Ukrainian air-defence systems had knocked out a total of 18 missiles, including types the Kremlin had touted as "ideal", as well as nine drones.
Reznikov later tweeted that Ukraine has officially joined the NATO Cooperative Cyber Defence Centre of Excellence (CCDCOE). He called it "yet another step towards common security space in Europe, which is impossible without Ukraine's membership in the Alliance".
Three people were injured in Kyiv and some rocket fragments fell on the capital's zoo but neither staff nor animals were hurt, Mayor Vitali Klitschko said.
Russia meanwhile said all the targets assigned by its military had been hit.
China's special envoy, Li Hui, was expected to arrive in Kyiv for a two-day visit as part of a European tour to promote Beijing-led negotiations to end the war in Ukraine.
A senior Ukrainian official, speaking on condition of anonymity, said Ukrainian authorities planned to further discuss Kyiv's stance on the conflict and China's peace mission.
"The president already said at the Vatican that we don't need mediation for the sake of mediation," the official told AFP, referring to President Volodymyr Zelensky's recent talks with Pope Francis.
He said the same message would be relayed to Beijing's envoy, insisting that "Ending the war with a compromise at the expense of Ukraine will not work".
- Graft crackdown -
Li will become the highest-ranking Chinese diplomat to visit the war-torn country since Moscow's invasion last year, three weeks after Zelensky spoke by telephone to Chinese leader Xi Jinping.
Xi, who has aimed to position China as a neutral mediator, and visited Moscow in March, has been criticised for refusing to condemn the Kremlin's attack on its neighbour.
Li's visit follows hot on the heels of Zelensky's whirlwind tour of major European capitals to urge allies to increase military support.
His tour to shore up military assistance to help make his troops more battle-ready began in Italy, with weekend visits to France and Germany, followed by a stop in the UK.
But Zelensky has yet to succeed in his goal of securing Western fighter jets to seize control of the skies, though UK Prime Minister Rishi Sunak announced preparations to open a flight school to train Ukrainian pilots.
Sunak and Dutch Prime Minister Mark Rutte, attending the CoE meeting in Iceland on Tuesday, pledged to build an "international coalition" to provide fighter jet support for Ukraine.
"The Prime Minister and Prime Minister Rutte agreed they would work to build (an) international coalition to provide Ukraine with combat air capabilities, supporting with everything from training to procuring F16 jets," a spokesman for Sunak's Downing Street office said in a statement.
France has also offered to train Ukrainian fighter pilots, though President Emmanuel Macron ruled out sending warplanes to Kyiv.
Nevertheless, Zelensky said late on Monday that he was "returning home with new defence packages".
Ukraine also announced Tuesday that it had detained the head of the country's supreme court in a $2.7 million bribery inquiry, part of anti-graft measures required for closer integration with the European Union.
Since Ukraine was officially granted candidate status by the EU last year following Russia's invasion, it has undertaken steps to clean up endemic corruption, including dismissing senior officials.
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