Part of the scandal surrounding President Trump's July conversation with Ukrainian President Volodymyr Zelensky involves Trump's decision to hold nearly $400 million in military aid ahead of their phone call, a story which continues to evolve.

On Monday, The Washington Post reported that officials with the Office of Management and Budget told the Pentagon and State Department that Trump had "concerns" about whether Ukraine really needed the money. The money was finally released in September, with Senate Republicans saying it was held up because the administration wanted to know if Zelensky was pro-Russia.

A senior White House official told the Post it was really blocked because of Trump's concerns regarding "a lot of corruption in Ukraine." After that report was published, Trump said he held the funding because he wanted "other countries to put up money. I think it's unfair we put up the money. Then people called me and said, 'Let it go.'"

NPR on Wednesday obtained a document showing yet another side of the story. In May, Undersecretary of Defense for Policy sent a letter to four congressional committees, letting them know that he "certified that the government of Ukraine has taken substantial actions to make defense institutional reforms for the purposes of decreasing corruption [and] increasing accountability." This letter was sent on behalf of the secretary of defense and in coordination with the secretary of state, with the certification necessary in order to release the military aid. Read the entire letter at NPR. Catherine Garcia