Russian troops are stepping up their efforts to secure full control of the entire Donbass region in eastern Ukraine – and from what we’ve seen, there’s very little to stop them right now, writes Sky’s special correspondent Alex Crawford . A huge chunk of the industrial heartland has already gone to the Russian military, allowing President Vladimir Putin to declare a major victory after his troops seized the Luhansk region by capturing the city of Lysychansk, the last Ukrainian stronghold there. The Russians already control most of Donetsk, the second half of Donbas, and signs are that they are moving to claim the rest. In recent days we have already seen increased attacks on the towns of Sloviansk and Bakhmut in the Donetsk region – and the frontline towns of Krasnohorivka and Marinka are also particularly vulnerable. The regions have been hotly contested for the past eight years and President Putin launched his “special military operation” in February after unilaterally declaring Donetsk and Luhansk “independent”. Ukrainian troops we spoke to told us time and time again that they feel outmatched and overwhelmed by the superior numbers of heavy Russian artillery they are being bombarded with. They hope the arrival of heavy artillery from America and Europe supplied from abroad can help them turn the tide, but it may have come too late for the Ukrainians to hold Donbas. We are the first British journalists to be given access to see the French-made Caesar shells now being used to try to contain the Russian army in the Donbas. French President Emmanuel Macron has already supplied 12 Caesars and after the G7 summit, pledged to supply six more. Heavy artillery is highly valued for its accuracy and can reach targets much further away – up to 30 miles away. Ukrainian troops from the 55th Brigade that we observed using the Caesars told us that the howitzers are much more versatile and give them a mobility that helps protect the crew. The gun can be ready to fire in about 60 seconds, and in even less time (about 40 seconds), it can be on the move again to keep away from enemy fire. The truck’s commander said his men spent 10 days learning how to operate the armored truck in France. “What we need is more weapons like this,” he told us. “More people to help us train. All we need is more ammo and then we’ll do everything else ourselves.” They know they’re on the back foot right now, but there’s still a very high level of optimism about the long-term future here, and he had this message for Russians who are still busy celebrating the capture of Luhansk. “Not for long,” says the commander. “We’re going to kick you out and take it all back.” Read her full story here.