In the meantime, on 1 April 1941, Rashid Ali Al-Gaylani launched a "coup d'état", which overthrew the pro-British regime in Iraq. The four generals leading the revolt worked closely with German intelligence and accepted military aid from Germany. Hitler asked Turkey for permission to pass through Turkish territory to give Iraq military assistance. In exchange, the Turkish government demanded border concessions from Iraq. As the negotiations were taking place, British forces attacked Iraq. Between 18 April and 3 June, Britain restored the regime of Emir Abdul-Illah, the regent of four-year-old King Faisal II. The issue between Turkey and Germany was resolved by that development. The German–Turkish Treaty of Friendship was signed on 18 June 1941.