Ukraine's presidential office said at least seven people were killed and 58 wounded in recent Russian attacks on Kherson.
Presidential office deputy head Kyrylo Tymoshenko announced the casualties on social media on Saturday. Ukraine retook the southern city from Russian forces last month.
Kherson regional prosecutors said Russian missiles targeted the densely populated city center.
Ukrainian President Volodymyr Zelenskyy said in a social media post that the locations attacked "are not military facilities. This is not a war according to the rules defined. It is terror."
He criticized Russia for continuing attacks on Ukrainian civilians during the Christmas holiday.
Hours earlier, Russia's presidential office rejected the possibility of observing a truce during the Christmas and New Year period.
Some analysts warn that Russian forces may carry out large-scale attacks in February or early in 2023.
The Wall Street Journal quoted Ukrainian and European diplomats as noting that Ukraine is considering presenting a peace plan around February 24, the first anniversary of Russia's invasion.
Zelenskyy has already proposed a 10-point peace plan that includes Russia's withdrawal from all Ukrainian territory.
The new plan is expected to demand large concessions from Russia.
Analysts say Ukraine is trying to prepare for such truce negotiations on the basis of winning the war with a winter offensive..