Washington (CNN) Rudy Giuliani traveled to Hungary and Ukraine this week to meet with several former Ukrainian prosecutors in an effort to defend President Donald Trump against House Democrats' impeachment inquiry, The New York Times reported Wednesday.

The Times, citing conversations with people familiar with the matter, said the President's personal attorney went to Budapest, Hungary, on Tuesday to meet with former Ukrainian prosecutor Yuriy Lutsenko, before going to Kyiv, Ukraine, on Wednesday to meet with a number of other former prosecutors in the country, including Viktor Shokin and Kostiantyn H. Kulyk. Giuliani, Trump's personal attorney and a key player in the President's dealings with Ukraine, traveled to speak with the former prosecutors for a documentary series meant to bolster unproven and debunked claims of corruption at the heart of the probe.

The ex-prosecutors have "all played some role in promoting claims" about former Vice President Joe Biden, former US Ambassador to Ukraine Marie Yovanovitch and Paul Manafort, Trump's former campaign chairman, the paper said. Those claims have been key to Trump and Giuliani's efforts to get Ukraine to announce investigations into matters that would benefit the President's 2020 reelection effort, according to House impeachment investigators.

When asked about the trip, Giuliani's spokeswoman Christianné Allen said his work was "still confidential."

"What Mr. Giuliani is doing at this point is still confidential and is for the sole purpose of proving his clients innocence. In doing so he will prove that this latest farce is even more baseless and malicious than the first attempted coup takedown. Once all individuals have returned safely to the United States, we will reveal the significant witnesses involved," said Allen in a statement to CNN.

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