Three administration officials are set to testify in public hearings, taking the impeachment investigation into new territory in accordance with a resolution passed by House Democrats late last month.

U.S. charge d'affaires in Ukraine Bill Taylor and Deputy Assistant Secretary for European and Eurasian Affairs George Kent are set to testify before Congress in a public hearing Wednesday. The officials will testify together at 10 a.m. ET.

Former U.S. Ambassador to Ukraine Marie Yovanovitch is scheduled to testify in public at 9 a.m. ET Friday.

President Donald Trump, meanwhile, has announced plans to "probably" release a transcript of an earlier conversation with Ukraine President Volodymyr Zelenskiy as soon as Tuesday.

The impeachment inquiry, led by House Intelligence Committee Chairman Adam Schiff, D-Calif., focuses on whether Trump abused his power by asking Zelenskiy in a July 25 call to "look into" former Vice President Joe Biden and his son Hunter — and investigate unsubstantiated allegations of Ukrainian interference in the 2016 U.S. presidential election. Trump's requests came as his administration held up a crucial military aid package to the country.

Here's what's coming up this week in the impeachment inquiry: