In his relations with the developing world, Gorbachev found many of the leaders professing revolutionary socialist credentials or a pro-Soviet attitude—such as Libya's Muammar Gaddafi and Syria's Hafez al-Assad—frustrating, and his best personal relationship was instead with India's Prime Minister, Rajiv Gandhi. He thought that the "socialist camp" of Marxist–Leninist governed states—the Eastern Bloc countries, North Korea, Vietnam, and Cuba—were a drain on the Soviet economy, receiving a far greater amount of goods from the Soviet Union than they collectively gave in return. He sought improved relations with China, a country whose Marxist government had severed ties with the Soviets in the Sino-Soviet Split and had since undergone its own structural reform. In June 1985 he signed a US$14 billion five-year trade agreement with the country and in July 1986, he proposed troop reductions along the Soviet-Chinese border, hailing China as "a great socialist country". He made clear his desire for Soviet membership of the Asian Development Bank and for greater ties to Pacific countries, especially China and Japan.