WASHINGTON — President Donald Trump directed US officials involved in Ukraine policy to work directly with his private lawyer Rudy Giuliani, the US ambassador to the European Union said on Thursday in prepared testimony to an impeachment inquiry against Trump.

The envoy, Gordon Sondland, will make the remarks to House of Representatives lawmakers pursuing the inquiry. Sondland said he did not understand "until much later" that Giuliani's agenda may have included a push for Ukraine to investigate former Vice President Joe Biden, a key political rival of Trump.

Sondland said he had been "disappointed by the President's direction that we involve Mr. Giuliani" and that it should be the work of the State Department and not the president's personal lawyer.

Sondland, a former Trump political donor, also said in the testimony that "inviting a foreign government to undertake investigations for the purpose of influencing an upcoming US election would be wrong."

Sondland's testimony underscored the pivotal role that Giuliani played in the Ukraine scandal. The impeachment inquiry centers on Trump's request on a July telephone call that Ukrainian President Volodymyr Zelenskiy investigate Biden, a leading contender for the 2020 Democratic presidential nomination to face Trump. Before that request, Giuliani had been working to engineer such an investigation.

In his testimony, Sondland said that on May 23, three days after Zelenskiy's inauguration, US officials who had attended debriefed Trump and key aides at the White House.

"We emphasized the strategic importance of Ukraine and the strengthening relationship with President Zelensky, a reformer who received a strong mandate from the Ukrainian people to fight corruption and pursue greater economic prosperity," Sondland said in the written testimony.

"We asked the White House to arrange a working phone call from President Trump and a working Oval Office visit. However, President Trump was skeptical that Ukraine was serious about reforms and anti-corruption, and he directed those of us present at the meeting to talk to Mr. Giuliani, his personal attorney, about his concerns," he added.

"It was apparent to all of us that the key to changing the President's mind on Ukraine was Mr. Giuliani," he added.

Sondland is the latest witness to speak to lawmakers about his knowledge of efforts by Trump to urge Ukraine to investigate former Vice President Joe Biden. Trump withheld $391 million in military aid to Ukraine before making the request.

— Reuters