President Volodymyr Zelenskyy on Saturday warned Ukrainians to be vigilant in the coming week as they prepare to celebrate their Independence Day, as fresh blasts hit Crimea and a missile wounded 12 civilians near a nuclear power plant.

In his nightly video address, Zelenskyy said Ukrainians must not allow Moscow to "spread despondency and fear" among them as they mark the 31st anniversary of independence from Soviet rule.

"We must all be aware that this week Russia could try to do something particularly ugly, something particularly vicious," Zelenskyy said ahead of the anniversary on Wednesday, which also marks six months since Russia's full-scale invasion of Ukraine began.