This is what Jeremy said as reported in The Guardian. It seems a fair point to me.
“Pouring arms in isn’t going to bring about a solution, it’s only going to prolong and exaggerate this war,” Corbyn said. “We might be in for years and years of a war in Ukraine.”
“What I find disappointing is that hardly any of the world’s leaders use the word peace; they always use the language of more war, and more bellicose war.”
He added: “This war is disastrous for the people of Ukraine, for the people of Russia, and for the safety and security of the whole world, and therefore there has to be much more effort put into peace.”