In 1953, the Communist government convicted the couple "in absentia" of "taking illicit leave" abroad. In 1956, the regime invited him back "with promises of freedom to do anything I wanted," said Kubelík, but he refused the invitation. In a 1957 letter to "The Times", Kubelík said he would seriously consider returning only when all the country's political prisoners were freed and all émigrés were given as much freedom as he would have possessed. He was invited back by the regime in 1966 but again refused; in 1968, after the Prague Spring had been ended by the Soviet invasion, he organised an international boycott, in which many of the major classical artists of the West participated.