As House Democrats step up their impeachment inquiries, President Trump sought to clarify via Twitter Wednesday night the context of his infamous July 25 phone conversation with his Ukrainian counterpart, President Volodymyr Zelensky.

Flashback: A memo of Trump's call with Zelensky shows the Ukrainian president brought up the possibility of buying more U.S. Javelin missiles for Ukraine's war against Russia, before Trump says: "I would like you to do us a favor though."

Trump then asked Zelensky to look into Ukraine's alleged involvement in the 2016 election, and to work with his personal lawyer Rudy Giuliani and Attorney General Bill Barr to investigate former Vice President Joe Biden and his son Hunter, who served on the board of the Ukrainian energy company Burisma.

Why it matters: The term "us" and what Trump meant by it is a central point in the impeachment inquiry.

While Trump insisted Wednesday he meant the U.S., House Democrats say in their draft report released Tuesday that he abused the power of his office to press Ukraine to investigate a potential 2020 rival to the benefit of his re-election campaign.

The Democrats concluded "that he obstructed Congress' authority by ordering witnesses to defy subpoenas in the impeachment inquiry," Axios' Alayna Treene notes.

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