HIROSHIMA: John Kerry, who on Monday became the first U.S. secretary of state to pay respects at Hiroshima's memorial to victims of the 1945 U.S. nuclear attack, described a museum there as "stunning" and "gut-wrenching" and said it was a reminder to all in public life to work for a world free of nuclear weapons.

Kerry, along with his counterparts from other Group of Seven (G7) advanced nations, toured the Hiroshima Peace Memorial and Museum, which displays photographs of badly burned victims, the tattered and stained clothes some of them wore and statues depicting them with flesh melting from their limbs.

His visit has raised speculation that U.S. President Barack Obama may become the first sitting U.S. president to visit Hiroshima when he travels to Japan for a G7 leaders summit in May.