Joseph Stalin, who identified Lange as a person of leftist and pro-Soviet sympathies, prevailed on President Franklin D. Roosevelt to obtain a passport for Lange to visit the Soviet Union in an official capacity, so that Stalin could speak with him personally; he also proposed offering him a position in the future Polish cabinet. The State Department was opposed to Lange traveling as an emissary because they felt that his political views represented neither Americans of Polish descent nor American public opinion in general. Lange's trip to the Soviet Union in 1944 caused further controversy, as the newly-establish Polish American Congress condemned him and defended the interests of the London-based Polish government-in-exile. Lange returned to the United States at the end of May and met, at Roosevelt's request, with Prime Minister Stanisław Mikołajczyk of the government-in-exile, who was on a visit in Washington. Lange stressed how reasonable Stalin was prepared to be (Stalin told him of the Soviet desire to preserve independent Poland under a coalition government), and asked the State Department to put pressure on the exiled Polish leadership to reach an understanding with the Soviet leader.