The Gestapo–NKVD conferences were a series of security police meetings organised in late 1939 and early 1940 by Germany and the Soviet Union, following the invasion of Poland in accordance with the Molotov–Ribbentrop Pact.

[1] The meetings enabled both parties to pursue specific goals and aims as outlined independently by Hitler and Stalin, with regard to the acquired, formerly Polish territories.

[5] Brześć was the location of the first Nazi-Soviet meeting organised on 27 September 1939,[1] in which the prisoner exchange was decided prior to the signing of mutual agreements in Moscow a day later.

From the Soviet side, several higher officers of the NKVD secret police participated in the meetings, while the German hosts provided a group of experts from the Gestapo.

[10] The first Gestapo–NKVD meeting took place in Brześć nad Bugiem (Brest) reportedly on 27 September 1939,[1] while some units of the Polish Army were still fighting (see: Invasion of Poland) resulting in mass internment of soldiers and their extrajudicial shootings on both sides of the Curzon Line.

They will suppress in their territories all beginnings of such agitation and inform each other concerning suitable measures for this purpose.Between 24 October and 23 November 1939, a total of 42,492 Polish prisoners of war were transferred from Kozelsk and Putyvl camps across the Nazi–Soviet demarcation line and handed over to the Germans.

[1][better source needed] According to several sources, one of the results of this conference was the German Ausserordentliche Befriedungsaktion (see: German AB Action operation in Poland),[14] elimination of Kraków intelligentsia Sonderaktion Krakau and the Soviet Katyn massacre[15] In his 1991 book Stalin: Breaker of Nations, British historian Robert Conquest stated: "Terminal horror suffered by so many millions of innocent Jewish, Slavic, and other European peoples as a result of this meeting of evil minds is an indelible stain on the history and integrity of Western civilization, with all of its humanitarian pretensions".

[18][19] Russian historian Alexandr Nekrich describes formal military cooperation agreement signed on 20 September 1939 where both sides committed to "cleansing of hostile population" and "liquidation" of Polish resistance.