Gordon Sondland, the U.S. ambassador to the European Union, told House committees during his impeachment inquiry testimony last week that he believes President Trump’s actions with regards to Ukraine amounted to a quid pro quo, The Wall Street Journal reports. According to Sondland’s attorney, Robert Luskin, the top diplomat told lawmakers that a meeting with Trump was contingent upon the Ukrainian president agreeing to open an investigation into Burisma—the gas company that Hunter Biden once sat on the board of. When asked by a lawmaker during his testimony if this exchange amounted to a quid pro quo, Sondland qualified that he is not an attorney, but that he believed it was a quid pro quo, according to Luskin.

Trump has repeatedly denied that there was a quid pro quo, and claimed that his decision to hold $400 million in aid intended for Ukraine was unrelated to any Ukraine investigation into the Bidens. In a text exchange with Bill Taylor, the acting U.S. ambassador to Ukraine, when the aid was initially withheld, Sondland wrote: “The President has been crystal clear no quid pro quo’s of any kind.” The assurance reportedly came after Sondland spoke directly to the president.