A major Russian missile attack struck a large children’s hospital in Kyiv Monday just as the ongoing war in Ukraine is set to be the major topic of conversation at the NATO leaders’ summit this week in Washington, D.C.

Prime Minister Justin Trudeau immediately condemned the attack as he arrived in the U.S. capital Monday morning.

“This is abhorrent,” he said in a statement.

“Striking a children’s hospital — and the innocent children inside — cannot be justified.”

The missile that struck Okhmatdyt children’s hospital was part of a daytime barrage targeting five Ukrainian cities. Officials said at least 31 people were killed and 154 injured, including at least seven children at the hospital.

Trudeau said Canada’s commitment to Ukraine remains as strong as ever. He is expected to send a message to NATO members during the leaders’ summit to bolster support for ongoing military aid for Ukraine.

NATO members have overwhelmingly provided support to Ukraine but have been cautious not to be drawn into a wider conflict with Russia.

NATO Secretary-General Jens Stoltenberg said Friday he expects heads of state and government will agree to a substantial package for Ukraine that “constitute a bridge to NATO membership.”

Some experts say its unlikely to go as far as Ukrainian President Volodymyr Zelenskyy hopes.