<h1>Long-term security partnership with Ukraine establishes enduring defence, technology and economic cooperation to bolster protection.</h1> British Prime Minister Keir Starmer pledged sustained support through a bilateral 100-Year Partnership treaty with Ukraine covering defence, science, energy and trade, emphasising defence collaboration (including maritime security in the Baltic, Black Sea and Sea of Azov), joint technology projects such as drones, mechanisms to track grain taken from occupied territory, and complementary UK financial assistance for Ukraine's postwar recovery.