For the first time, Ukraine President Volodymyr Zelensky joined a meeting of more than 50 defense leaders from around the world on Wednesday to make a personal pitch for military aid, in the face of lagging political support in the US and new pressure on allies to send weapons to bolster Israel’s war with Hamas.

His presence underscored growing concerns about cracks in what has been staunch international backing for Kyiv in its war against Russia’s invasion, and worries that Ukrainian forces haven’t made measurable progress in the counteroffensive, as winter closes in.