What does Ezekiel 31:15 mean?

This is what the Lord God says: When the cedar went down to the grave, I made the deep waters mourn for it. I stopped its rivers, and the great waters were held back. I made Lebanon mourn for it, and all the trees in the fields dried up because of it. Ezekiel 31:15 - Modern Text Bible

(Assyria’s fall affected everyone around it, causing widespread grief and loss.)