The letter lays out Putin's increasingly apparent vulnerabilities, Ukraine's growing strength, and the case for an immediate reopening of peace negotiations.

Ukrainian President Volodymyr Zelenskyy has called for face-to-face negotiations with Russian President Vladimir Putin.

"Almost half of your 26 years of power in Russia you have spent in the war against Ukraine," Zelensky wrote to Russian President Vladimir Putin. "Whatever you say about NATO,…