Kiev, June 6 : Ukraine's Deputy Defence Minister Hanna Maliar has confirmed that troops were making advances on the eastern front around the city of Bakhmut, which she described as the "epicentre of hostilities". Without confirming if the much-awaited Ukrainian counter-offensive had started, the Minister in a social media post on Monday said that "despite stiff resistance and the enemy's attempts to hold the their positions, our military units advanced in several directions during the fighting", the BBC reported. She said in Orikhovo-Vasulivka and Paraskoviivka, Ukrainian troops gained from 200m to 1,600m, while in Ivanivske and Klishchiivka they advanced between 100m and 700m. All four villages are located within several kilometres of Bakhmut and the battle for the city in the Donetsk region has been the longest and bloodiest of the war that began in February 2022. On Tuesday night in his regular video message to the nation, President Volodymr Zelensky thanked Ukrainian fighters for delivering "the news we are expecting" on the Bakhmut direction. "The enemy knows that Ukraine will win. They see it. They feel it thanks to your strikes, soldiers, and in particular in Donetsk region," he said. In the early hours of Tuesday, air raid sirens were activated all over Ukraine, with officials in Kiev reporting that air defence systems were in operation in the capital region. Also on Tuesday morning, the Russian Defence Ministry said that Ukrainian forces had carried out a military operation in southern Donetsk on Monday in an attempt to advance, but it was stopped after the Ukrainians suffered "heavy losses", reports CNN. On Monday, Ukrainian forces were "hit with a complex weapons strike by the army forces, assault and operational-tactical aviation, missile forces, and artillery, as well as heavy thermobaric systems", the Ministry saidon its Telegram channel. It also claimed Russian forces destroyed "28 tanks, including eight main battle Leopard tanks", and 109 armoured fighting vehicles. Russia's claim has not been verified by Ukraine so far. Bakhmut has for months been at the heart of fierce fighting. It has little strategic value, but is important symbolically both for Kiev and Moscow. Late last month, the Russian mercenary Wagner group had claimed to have captured the city. Despite Wagner's claims, Ukraine has not conceded that the eastern city has fallen. In May, the US said that it believed more than 20,000 Russian soldiers had been killed in the battle for Bakhmut and another 80,000 wounded. Ukraine however, has not released figures on its casualties in Bakhmut, but has also sustained heavy losses. The capture of Bakhmut would bring Russia slightly closer to its goal of controlling the whole of Donetsk, one of four regions in eastern and southern Ukraine annexed by Russia last September following referendums widely condemned outside Russia as a sham. However, when Russia fought fiercely to claim the cities of Severodonetsk and Lysychansk last summer, Ukraine soon reclaimed swathes of territory elsewhere. There were about 70,000 people living in Bakhmut before the invasion, but only a few thousand remain in the devastated city, once best known for its salt and gypsum mines and huge winery. /IANS