President Zelensky has called Ukraine's air defence supplies "insufficient", having revealed several systems were "without missiles" until Friday morning.
"I can say this openly because today I have those missiles," the president said, adding that the country had received a "substantial package" earlier in the day.
His comments follow days of intense Russian bombardment of Ukraine's energy infrastructure, which has left thousands of people without heating and electricity during a bitterly cold winter.
Schools in Kyiv will shut until February, the capital's mayor announced later in the day, as the city continues to face severe energy shortages amid temperatures which have dropped as low as -19C.
Zelensky called on Ukraine's allies to provide "rapid deliveries" of available missiles, and said shipments did not mean "that winter will end for us tomorrow".
