On April 25, 1944, as a desperate measure to increase the supply of goods into the country, the Nazis offered to permit one million Jews to leave Hungary in exchange for goods obtained outside of Hungary. Included in this deal was a request for 10,000 trucks for civilian use or for use along the eastern front. Adolf Eichmann said, "When the 10,000 winterized trucks with trailers are here, then the liquidation machine in Auschwitz will be stopped."
Eichmann and the upper echelons of the SS, including Heinrich Himmler approved this proposal which would allow the Jews to leave Hungary for any Allied-occupied country, with the exception of Palestine. (The Nazis had promised the Grand Muflti Hajj Amin Al-Husseini that he would prevent Jewish immigration to Palestine).
The Nazis chose Joel Brand, a member of the Relief and Rescue Committee of Budapest (also known as the Va'ada) to assist them in negotiations with world Jewish leaders and the Allied governments. Also chosen to manage negotiations with the Allies was Andor Grosz, a minor intelligence agent and employee of both the Va'ada and the SS at different times. Grosz was supposed to lead a different set of discussions: A separate German truce with the Western allies. Brand was a decoy to distract the allies from Grosz's more important mission.
The offer was not seriously considered because the Allies believed it to be a trick and did not want to negotiate with the Nazis. The British press stirred up opposition to the proposal, calling the "monstrous offer" to exchange goods for Jews blackmail.
Several considerations factored into the decision of the Allies to dismiss the deal: Soviet opposition of the idea; British hesitancy to absorb that number of Jewish immigrants should the Nazis really permit them to emigrate; and the continuation of the Final Solution in Hungary.
After the Allies learned of the plan, Grosz was arrested and unable to complete his assignment. Brand left for Palestine but was arrested on June 5, 1944. Still under arrest, the British allowed him to speak with Moshe Shertok (Sharett) five days later, then head of the Jewish Agency's Political Department about the deal, and Shertok tried to promote support for it.
After his meeting with Shertok in June, Brand was imprisoned in Cairo until October and then allowed into Palestine. For a long time he believed that the Allies were at fault for not allowing the exchange to take place, but toward the end of his life he decided that Himmler's true intentions were to distract the Allies, and in the meantime, create a Nazi-western coalition against Moscow.
This was not the end of the story. Rudolf Kasztner became the chief contact with Eichmann in place of Brand, whom Eichmann had sent to Istanbul to open negotiations with Jewish leaders abroad. According to Eichmann, Kasztner was a "fanatical Zionist" who "agreed to keep the Jews from resisting deportation--and even keep order in the collection camps--if I would close my eyes and let a few hundred or a few thousand young Jews emigrate illegally to Palestine. It was a good bargain. For keeping order in the camps, the price of 15,000 to 20,000 Jews--in the end there may have been more--was not too high for me.
In the period of August 21, 1944–April 1945, Kasztner visited Germany several times, and went five times to Switzerland, to meet representatives of the American Jewish Joint Distribution Committee and the Jewish Agency on the rescue plan, and particularly to arrange its financing by Jewish organizations. These activities resulted in the Germans’ transfer to Switzerland of two transports, first of 318 and later of 1,368 Jews from Bergen-Belsen, most of them of Hungarian and Transylvanian origin (on August 18 and December 6, 1944). Kasztner’s negotiations with the Germans were meant to ensure the survival of the Jews in the Budapest ghetto.
After the war, while living in Israel, Kasztner was accused of collaborating with the Nazis.