World leaders and top-ranking officials convened Monday in Geneva for a new session of the U.N. Human Rights Council, set to run thought April 4. The role of the United Nations in holding Moscow accountable for war crimes is set to be a key topic of debate. A delegation from Moscow, which was expelled from the main U.N. human rights body in April over violations in Ukraine, is participating as an observer, Reuters reported, in the first in-person appearance by a Russian official since the war started.