He toured with the IPO in the spring of 1990 for their first-ever performance in the USSR , with concerts in Moscow and Leningrad , and toured with the IPO again in 1994 , performing in China and India . He toured with the IPO in the spring of 1990 for their first-ever performance in the Soviet Union , with concerts in Moscow and Leningrad , and toured with the IPO again in 1994 , performing in China and India .