President Vladimir Putin said Friday that Russia will continue to test and start mass-producing the hypersonic ballistic missile that it fired at Ukraine Thursday.

The experimental strike Thursday marked a decisive moment in Moscow’s war and capped off a dramatic week that has transformed the conflict. The firing of the missile came after the White House authorized Ukraine to fire its long-range missiles into Russia.

In a televised meeting with the leadership of Russia’s defense ministry, Putin claimed the missile could not be intercepted by air defenses and said Russia will begin serial production of the new weapon.

“There are currently no means of countering such a missile, no means of intercepting it, in the world. And I will emphasize once again: We will continue testing the latest system,” Putin said.

Putin added Russia was developing “several similar systems” for further testing.

“Based on the test results, these weapons will also go into production. That is, we are developing a whole line of medium- and shorter-range systems,” he said.

Putin’s comments come a day after Russia fired the “Oreshnik” missile – which contains multiple warheads – at the Ukrainian city of Dnipro.

Ukrainian President Volodymyr Zelensky condemned the attack, saying in a video posted on Telegram that “today, our crazy neighbor has once again shown who he really is and how he despises dignity, freedom and human life in general.”

Zelensky said Friday that Ukraine was holding meetings with its allies about developing “new air defense systems” in response to the new threat from Russia.

Poland’s Prime Minister Donald Tusk, a key ally of Ukraine, said the conflict was “entering a decisive phase.”

NATO and Ukraine are due to hold talks next week following Russia’s firing of the experimental missile.