Lithuania declared sovereignty on its territory on 18 May 1989 and declared independence from the Soviet Union on 11 March 1990 as the Republic of Lithuania, and was the first Soviet republic to do so. All legal ties of the Soviet Union's sovereignty over the republic were cut as Lithuania declared the restitution of its independence. The Soviet Union claimed that this declaration was illegal, as Lithuania had to follow the process of secession mandated in the Soviet Constitution if it wanted to leave. Most other countries followed suit after the failed coup in August, with the State Council of the Soviet Union recognized Lithuania's independence on 6 September 1991.