Ukrainian President Volodymyr Zelenskyy has urged the world not to wait for Russia to use nuclear weapons. He stressed the need to prepare for such an attack by taking measures such as building bomb shelters.

Zelenskyy aired the appeal in a video on Saturday.

He underscored the need for talks and a further squeeze on Russia's economy to discourage the country from resorting to nuclear arms.

Zelenskyy said Russia is untrustworthy and could use any weapons it has.