The United States marshaled 40 allies on Tuesday to furnish Ukraine with long-term military aid in what could become a protracted battle against the Russian invasion, and Germany said it would send dozens of armored anti-aircraft vehicles. It was a major policy shift for a country that had wavered over fear of provoking Russia.

The announcement by Germany, Europe’s biggest economy and one of Russia’s most important Western trading partners, was among many signals on Tuesday pointing to further escalation in the war and disappointment for diplomacy.

Germany’s shift on weapons also was seen as a strong affirmation of a toughened message by the administration of U.S. President Joe Biden, which has said it wants to see Russia not only defeated in Ukraine but seriously weakened from the conflict that Russian President Vladimir Putin began two months ago.