A former Ukrainian prosecutor who investigated a gas company tied to Hunter Biden said Thursday that there was no evidence the former vice president's son engaged in illegal activity.

"From the perspective of Ukrainian legislation, he did not violate anything,” Yuriy Lutsenko told The Washington Post.

Lutsenko, who served as Ukraine's prosecutor general from May 2016 until last month, closed the investigation into the gas company Burisma and its oligarch owner in 2017, The New York Times has reported. Earlier this year, Lutsenko met with President Donald Trump's personal lawyer, Rudy Giuliani, and discussed Burisma, Lutsenko's spokeswoman told Bloomberg. Then in March, according to the Times, Lutsenko reopened an investigation into the company, though his spokeswoman has disputed that.

The meetings with Giuliani were referred to in a bombshell whistleblower complaint unsealed Thursday that alleged that Trump had pressured the Ukrainian president to investigate the Bidens.

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In May, Lutsenko told Bloomberg News that his office had found no evidence of wrongdoing against Hunter Biden or his father, Joe Biden, who'd helped to oust Lutsenko's predecessor.

That prosecutor, Viktor Shokin, had been accused of failing to act in numerous corruption cases, including the investigation into Burisma. In addition to the United States government, the European Union and the International Monetary Fund have demanded that Shokin be replaced.

On Thursday, Lutsenko said he did not know of any Trump administration officials going to Ukraine to investigate the claims against the Bidens.

“No American groups came to Ukraine for an investigation,” he told the Post.

Lutsenko added that whatever wrongdoing there might have been at Burisma took place before Hunter Biden joined the company.

“Hunter Biden cannot be responsible for violations of the management of Burisma that took place two years before his arrival,” Lutsenko told the Post.