(Reuters) -Russian forces attempted to storm the Ukrainian-held Azovstal steel plant in the besieged southeastern city of Mariupol on Sunday, Ukrainian officials said, despite Russian President Vladimir Putin’s comments last week that the complex did not need to be taken. Ukraine’s armed forces command wrote on Facebook that Russian forces were firing and performing “offensive operations” in the Azovstal area, as well as conducting air strikes on civilian infrastructure. Serhiy Volyna, commander of Ukraine’s 36th Marine brigade forces in Mariupol, said in an interview with an opposition lawmak…