By Philip Pullella VATICAN CITY (Reuters) -Pope Francis on Sunday described the war in Ukraine as a “macabre regression of humanity” that makes him “suffer and cry”, calling for humanitarian corridors to evacuate people trapped in the Mariupol steelworks. Speaking to thousands of people in St. Peter’s Square for his noon blessing, Francis again implicitly criticised Russia. In Roman Catholicism, the month of May is dedicated to Mary, the Mother of God. Francis asked for month-long prayers for peace in Ukraine. “My thoughts go immediately to the Ukrainian city of Mariupol, the city of Mary, bar…