Ukraine war: US confirms 'communications' with Kremlin- PublishedUS National Security Adviser Jake Sullivan has confirmed communication channels between Washington and Moscow remain open.US National Security Council spokeswoman Adrienne Watson refused to confirm the story, telling the paper that "people claim a lot of things", while Kremlin spokesperson Dmitry Peskov accused Western newspapers of "publishing numerous hoaxes".But Mr Sullivan told a public event in New York that the Biden administration had "an obligation to pursue accountability" and pledged to work with international partners to "hold the perpetrators of grave and grotesque war crimes in Ukraine responsible for what they have done".and I had the opportunity to meet with President [Volodymyr] Zelensky and my counterpart Andriy Yermak, with the military leadership and also to get a briefing on just what level of death and devastation has been erupted by Putin's war on that country," Mr Sullivan said.Concerns have been heightened in recent months that Russia could resort to using nuclear weapons in a desperate attempt to defend four regions of eastern and southern Ukraine that it illegally annexed."