The US and British political and commercial roles in contributing to funding the Nazi Party and later the Third Reich was well documented by documentary filmmaker Michael Romm, and academics like Antony Sutton and Jacques R. Pauwels.

US officials and Wall Street traders planned to covertly loan billions of dollars to Nazi Germany just before the Second World War and attempted to hide their plans, according to information gathered by the foreign intelligence division of the NKVD, the SVR's predecessor.

A report from the NKVD from the summer of 1939 written by an undercover field agent detailing "the participation of statesmen of the USA and Great Britain in financial transactions in aid of Nazi Germany" is one of a vast collection of documents that have been declassified, digitalized, and published on the website of the Boris Yeltsin Presidential Library about the years preceding World War II.

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The document describes how Soviet intelligence learned about efforts to conceal American involvement in a planned multi-billion dollar loan from London to the Third Reich on July 24, 1939, just over a month before the Nazi invasion of Poland, through one of its informants.

“All American newspapers reported on a conversation between Sir Robert Hudson [the UK Secretary of Overseas Trade], and [a] German economic advisor…on the question of a five billion dollar British loan to Germany,” the report indicated, citing former president Herbert Hoover’s suspected “direct involvement” and “interest” in the Anglo-German agreement.

The document noted that Hoover had Wall Street's support in terms of US foreign and domestic policy, and that he could offer “substantial support for the implementation of Hudson’s negotiations with the Germans."

The intelligence assessment also stated that "urgent efforts" were made to collect materials linked to the intended loan after these press reports, out of fear for the political fallout they might generate for Hoover and the Republican Party.

Three folders containing materials related to the loan were said to have been confiscated by Hoover advisor and businessman Francis White.

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According to the paper, Hoover was terrified that his identity would be revealed to the media in connection with the loan. Hudson was instructed to keep the transaction under "strictest secrecy" and to withhold the names of those involved in the "London property," the codename for the loan.

The declassified document provides new insight into the Kremlin's knowledge of the US and British alliance with Hitler, as well as Moscow's calculations in the summer of 1939 when it decided to forgo stalled talks with Britain and France on the formation of a tripartite alliance against Nazi Germany in favor of a non-aggression pact with Berlin to buy time for the USSR's rearmament and military reorganization.

The document is just one of a series of prewar and wartime intelligence reports featured in the trove of digitized materials.