this is bbc news. our top stories: police launch an investigation into whether parties at downing street violated covid rules. a spokesman says borisjohnson didn't think he had broken the law. more tough talk over ukraine — president biden says he'd consider personal sanctions on vladimir putin if russia invaded ukraine at least 46 people are killed as tropical storm ana hits madagascar and mozambique. thousands have had to leave their homes. coronavirus breaks out among crew on an aid ship headed for tonga, hampering relief efforts as authorities try to keep the islands covid—free.