Russian President Vladimir Putin has called on Ukrainian troops in the Russian region of Kursk to surrender, as diplomatic back-and-forth continues over a potential US-brokered ceasefire with Ukraine.

Russian forces have almost completely surrounded Ukrainian troops in Russia’s Kursk region, with some Ukrainian units forced to leave their vehicles behind as they pull back, according to a U.S. military official.

A strong Ukrainian force invaded Kursk in August, aiming to seize a swathe of Russian soil that Ukrainian President Volodymyr Zelensky could eventually trade back to Russian Presi