Ukraine’s president pledged to push for victory in 2023 as he and other Ukrainians on Friday marked the somber anniversary of the Russian invasion that he called “the longest day of our lives.”

As morning broke on a day of commemorations and reflection, President Volodymyr Zelenskyy struck a tone of grim defiance and used the Feb. 24 anniversary to congratulate Ukrainians on their resilience in the face of Europe’s biggest and deadliest war since World War II. He said they had proven themselves to be invincible in what he called “a year of pain, sorrow, faith and unity.”

“We survived the first day of the full-scale war. We didn’t know what tomorrow would bring, but we clearly understood that for each tomorrow, you need to fight. And we fought,” he said in an early morning video address.

It was “the longest day of our lives. The hardest day of our modern history. We woke up early and haven’t fallen asleep since,” he said.