Russian President Vladimir Putin launched his invasion of the Eastern European country on February 24 and was met with a strong defensive effort from Ukraine, bolstered by military aid from its allies. Despite the sheer size of the Russian army, Moscow failed to achieve any major goals. Ukrainian forces have launched counterattacks in recent days in Kherson and the Kharkiv region in an attempt to retake territory. On Saturday, Ukrainian troops made significant gains near Kharkiv, the second-largest city in Ukraine—forcing Russia to retreat from key cities including Izium and Kupyansk, according to Radio Free Europe. Girkin, who also goes by Igor Strelkov, has long been seen as an anti-Ukraine hardliner. However, he acknowledged Ukraine’s victory in a Telegram post on Saturday. Above, Igor Girkin, who is also Igor Strelkov, delivers a news conference in Donetsk on July 28, 2014. Girkin on Saturday said Russia suffered a “big defeat” after Ukraine recaptured the city of Kupyansk. BULENT KILIC/AFP via Getty Images He wrote that Russia had suffered a “major defeat” in Kharkiv amid reports that Russian troops had abandoned Kupyansk, which has served as a major rail and logistics hub for the Kremlin since it seized the city in February. Britain’s Ministry of Defense said on Saturday that Ukraine’s recapture of the city would deal a “significant blow” to Russia. In his post, Girkin added that because Ukraine has “already won,” Russia should now focus on maintaining its troops. “Now, in fact, our side can only talk about how to stop its further deepening and prevent an operational defeat from escalating into a strategy,” he wrote. “Although, in general, it has already been overcome. “Battle for the initiative” the enemy has already won. Now we need to talk about preventing the Armed Forces of Ukraine from encircling and destroying large formations of our troops.” The Ukrainian victories at Kupyansk and Izium come just a day after Girkin said Russian troops had only one or two days to launch counterattacks against Ukraine at Izium or face defeat. “The question of the timing of the counterattack is very acute: if the enemy manages to gain a foothold in the positions he has reached, draw artillery and air defense, then it will be extremely difficult for our units to throw him back…. if at all (given extremely low staffing, especially infantry) Maybe,” he wrote in a Friday Telegram post. On Saturday morning, Russian forces also withdrew from Izio, according to Russia-based First Deputy Minister of Information of the DPR Danilo Bezhsonov, who described the situation as “bad”. British defense officials said the counterattack in Kharkiv likely caught Russia by surprise. After launching the counteroffensive on Tuesday, Ukrainian forces advanced more than 30 miles into territory previously held by Russia. Ukrainian President Volodymyr Zelensky said during a speech on Friday night that Ukrainian forces “liberated and took control of more than 30 settlements” in the Kharkiv region. Newsweek has reached out to the Russian Defense Ministry for comment.