Russia on Thursday launched an intercontinental ballistic missile toward Ukraine, officials in Kyiv said, but a Western official told ABC News that the attack did not appear to be an ICBM.

It was instead a ballistic missile, which was aimed at Dnipro, in Ukraine’s southeast, the Western official said.

The claim was not immediately confirmed by Moscow, with Kremlin spokesperson Dmitry Peskov declining to comment, saying questions about it should be instead directed to the Russian Defense Ministry.

The launch of an ICBM, if confirmed, would arrive amid concerns that the conflict between Russia and Ukraine could escalate. Ukraine’s military this week first launched U.S.-made ATACMS missiles toward targets within Russia, days after U.S. President Joe Biden allowed for such use of the long-range weapons.

Within hours of Russia announcing it had struck down some of those ATACMS missiles, the Kremlin announced that Russian President Vladimir Putin had updated the country’s nuclear doctrine, a move that lowered the bar for a response with nuclear weapons.