WASHINGTON — House Speaker Nancy Pelosi plans to announce a formal impeachment inquiry into President Donald Trump on Tuesday, acquiescing to mounting pressure from Democratic lawmakers following reports that Trump may have sought a foreign government’s help in his reelection bid.

The decision sets up an election season clash between Trump and Congress that seems certain to exacerbate the nation’s fierce partisan divides and inject deep uncertainty into the 2020 presidential contest.
Pelosi was huddling with her caucus Tuesday afternoon and planned to announce the impeachment probe in a statement following the meeting. Her plans were confirmed by a person familiar with her thinking, who insisted on anonymity because they were not authorized to speak publicly.
Pelosi has spent months trying to keep an impeachment inquiry at bay. But her position became untenable this week as more members — including crucial moderates in political swing districts — swung in favor of a probe following reports that Trump pushed Ukraine’s leader for help investigating Democrat Joe Biden and his son during a summer phone call.
Trump said he had authorized the release of a transcript of the call on Wednesday.
“You will see it was a very friendly and totally appropriate call,” Trump said.