Ukraine’s Parliament canceled a session on Friday over a warning that Russia could target the building in an attack with a missile that Ukraine’s air defenses cannot shoot down, lawmakers said.

Although they did not say which type of missile they were worried about, the decision to cancel the session came a day after Russia fired what it described as a new, intermediate-range missile. Ukraine has no radars capable of detecting those missiles in flight through the upper atmosphere, nor air defense systems capable of shooting them down, Ukrainian experts have said.

Since the start of the war, Parliament has continued meeting in its chambers, even in the first months of the conflict, when Russian forces were just 12 miles from the center of the capital. But on Friday, Parliament decided not to take the risk.

“They canceled it late last night, citing the danger of a missile strike,” Oleksiy Honcharenko, an opposition member of Parliament, said of the planned session.

The intermediate-range missile launched Thursday carried conventional warheads, but it is also capable of carrying nuclear weapons, and analysts and Western officials said the purpose was to instill fear in Ukraine and the West.

President Vladimir V. Putin of Russia on Thursday said his forces used the missile in response to Ukraine’s using American and British weapons in strikes further into Russia.