Read: Text messages between US diplomats about Ukraine aid, Trump phone call

Text messages released by House Democrats amid an impeachment inquiry detail a top U.S. diplomat's concerns about a Trump White House strategy aimed at pressuring Ukraine for political investigations in exchange for assistance and engagement with Trump. 

The messages are between Kurt Volker, former U.S. special envoy to Ukraine, and William Taylor, Jr., top ambassador to Ukraine; as well as Gordon Sonland, U.S. ambassador to the European Union; Andrey Yermak, aide to Ukrainian President Volodymyr Zelensky; and Rudy Giuliani, Trump's attorney.

Reps. Adam Schiff, Elijah Cummings and Eliot Engel released the text messages. The information was provided by Volker.

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