U.S. Ambassador to the European Union Gordon Sondland was in communication with individuals close to Ukrainian President Volodymyr Zelensky in mid-May about investigations the Trump administration wanted the country to pursue, according to two individuals with knowledge of those conversations.

That fact was transmitted to senior White House officials the same month, including former top Russia adviser Fiona Hill, those sources said, raising concerns that the policy the U.S. presented publicly on Ukraine was at risk of being derailed. The details disclosed to The Daily Beast here show Sondland was involved in efforts to speak with top Ukrainian representatives about the investigations earlier than previously reported and before his first publicly known meeting on Ukraine with President Donald Trump.

The Associated Press has previously reported that as of the beginning of May staffers at the U.S. Embassy in Kyiv were briefed on a meeting Zelensky, then president-elect, held in which he sought advice on how to handle the demands by the Trump administration to investigate 2020 presidential candidate Joe Biden and his son Hunter. The Daily Beast, too, reported that top Ukrainian officials were concerned in May about the timeline for the delivery of U.S. military aid to the country. But it has been unclear—until now—when Sondland, one of the key characters in the House impeachment inquiry, first began trying to convince the Ukrainians to work with the U.S. in launching investigations into the Bidens.

Sondland, along with Energy Secretary Rick Perry and former top diplomat for Ukraine Kurt Volker, met with Trump at the White House May 23 following their trip to Kyiv for Zelensky’s inauguration. Acting Chief of Staff Mick Mulvaney and Trump instructed the crew—then dubbed “the three amigos”—to work with Trump’s personal attorney Rudy Giuliani on all matters related to Ukraine. Sondland worked with the Zelensky team before that meeting, sources said, and had spoken with aides about the need for investigations into the country’s energy sector.

Sondland is set to testify Wednesday morning in front of House impeachment investigators about his work on Ukraine and his direct communication with Trump on U.S. policy with Kyiv. Several of his State Department colleagues, as well as top national security officials, have testified in an open setting that Sondland sat at the center of the Trump administration’s efforts to convince Ukraine to launch investigations not only into the Bidens but also into the 2016 presidential election in exchange for a Zelensky White House visit.

Sondland raised the topic of investigations at a controversial meeting on July 10 at the White House. Several house impeachment witnesses have said Sondland told the Ukrainian officials present at the meeting that they needed to launch the investigations if they wanted Zelensky to meet Trump at the White House. The Daily Beast reported Sunday that Sondland became emotional in the Ward Room meeting, at times outright demanding the Ukrainians agree to the investigations.

The EU ambassador at several different points told his colleagues that he was in contact with Trump directly. Last week House impeachment investigators received testimony from Kyiv embassy staffer David Holmes that he overheard Sondland speaking with Trump about Zelensky and the Biden investigations July 26. He told Trump that Zelensky “loves your ass” and that the president of Ukraine would do anything Trump wanted him to do, Holmes said.

It’s unclear exactly how Sondland will perform during his hearing. A mega-donor to Trump’s inauguration, Sondland will likely try to protect any information involving his conversations with the president. But that doesn’t mean Trump will look favorably upon Sondland during his testimony. Trump has repeatedly condemned House impeachment witnesses during their appearance in front of the intelligence committee, at times denouncing them as “never Trumpers.”

On Tuesday, the Trump White House took the extraordinary step of blasting out talking points to surrogates and conservative media allies attacking the credibility, conduct, and judgment of Lt. Col. Alexander Vindman, a current White House official who publicly testified that day.

If Sondland steps too far out of line during the hearing, he should expect a similar flogging from the administration in which he still serves. Three people familiar with preparations within Trumpworld, including in the West Wing, say that there have been plenty of planning discussions among officials and the president’s advisers about options for potential messaging retaliation against Sondland, if the occasion of his testimony calls for it. The sources declined to go into detail of what official responses were discussed.