At a ceremony opening the G7 summit in Japan, leaders laid wreaths and visited the museum commemorating the 1945 attack

• G7 leaders prepare new sanctions against Russia

G7 leaders have laid flowers at a memorial to the victims of the US atomic bombing of Hiroshima in a sombre opening to a summit overshadowed by fears of a potential nuclear conflict in Ukraine.

As the heavy early morning rain began to ease, the summit’s host, Japanese prime minister Fumio Kishida, and his wife, Yuko, welcomed leaders and their spouses at the entrance to the city’s Peace Memorial Museum, where they viewed graphic reminders of the attack on the city on 6 August 1945 and its gruesome aftermath.