this is bbc news. welcome if you're watching here in the uk or around the globe. iamjoanna i am joanna gosling. our top stories... air—raid sirens sound in cities across ukraine, including in the capital, kyiv, as russia pushes into new areas. the president remains defiant. translation: i assure you that 100% of all people in all— democracies will know this. the actions of the russian invaders will be equated with the actions of isis terrorists. ukraine says it hopes a number of humanitarian corridors from the besieged city of mariupol will open up, and accused russia of blocking supplies. iam i am yalda hakim, live in the western city of lviv where tens of