Ukrainian forces repelled a Russian offensive on the southern front following the withdrawal of Kyiv's troops from the devastated eastern town of Avdiivka, the Ukrainian military said on Sunday. Ukraine's army chief Oleksandr Syrskyi said on Saturday that Kyiv's troops withdrew from Avdiivka to avoid encirclement following months of fierce Russian attacks, Moscow's biggest advance since its troops captured the city of Bakhmut last May.