The FBI investigation into Rudy Giuliani is focused on Trump's firing of the US ambassador to Ukraine, NYT says

• The FBI probe of Rudy Giuliani centers on the firing of the US ambassador to Ukraine, The Times reported.
• Agents seized Giuliani's electronic devices in a 6 a.m. raid and are searching them for evidence.
• The firing of Marie Yovanovitch was scrutinized in Donald Trump's first impeachment trial.

The FBI's investigation into Rudy Giuliani's dealings in Ukraine is focused on the 2019 firing of Marie Yovanovitch, the US's ambassador to Ukraine, The New York Times reported on Thursday.

A source told the publication that federal agents were scouring Giuliani's electronic devices for communications with the Trump administration about Yovanovitch's firing in May 2019.

They are also examining his communications with Ukrainian officials hostile to Yovanovitch, The Times' sources said.

Federal agents raided Giuliani's offices and apartment in Manhattan on Wednesday. Giuliani described answering the door at 6 a.m. to agents who searched the property looking for electronic devices.

They are seeking to establish whether Giuliani was working on behalf of Ukrainian individuals when he lobbied the administration for Yovanovitch's firing.

Read more: Trumpworld shuns Rudy: The inside story of Giuliani's descent from 'America's mayor' to presidential lawyer and now an FBI target

In an interview with Fox News on Thursday, Giuliani denied any wrongdoing.

"I've never represented a Ukrainian national or official before the United States government," Giuliani said.

Yovanovitch's firing was a key event in President Donald Trump's first impeachment.

Trump had dispatched Giuliani, his attorney, to Ukraine in 2019.

Giuliani was looking for material on Hunter Biden, the son of Joe Biden, then a Democratic presidential candidate. Hunter Biden had been on the board of a Ukrainian energy firm when his father was the vice president.

Giuliani had claimed that Yovanovitch was disrupting his investigation.

Giuliani's ties with Ukrainian officials seeking to help his search have come under scrutiny. US intelligence officials are said to believe that some of Giuliani's contacts were Russian agents pushing disinformation about the Bidens.

The bid to uncover damaging information about the Bidens in Ukraine led to Trump's first impeachment. Democrats argued that the president abused his power by pressuring Ukraine's president to lend credibility to the accusations by announcing an investigation into them.

The Republican-controlled Senate acquitted Trump in January 2020.