(Bloomberg) -- House Speaker Nancy Pelosi said President Donald Trump’s actions raise a “compelling national security issue” that will be the focus of an impeachment inquiry in Congress.

“We have to stay focused as far as the public is concerned, that the president of the United States used taxpayer dollars for a shake down” of a foreign leader, Pelosi said in an interview on MSNBC’s “Morning Joe” on Friday.

Pelosi said that Trump appeared to have been disloyal to his oath of office in “jeopardizing our elections” by asking a foreign leader to dig up dirt on a political rival. She said that the probe will be focused in the House Intelligence Committee under Chairman Adam Schiff, a Democrat from California. She said they will move “expeditiously” but “not hastily.”

“This is no cause for joy,” Pelosi said, adding that it is “a sad time for our country.”

Democrats pursuing Trump’s removal from office have been emboldened by a whistle-blower complaint released on Thursday that alleges Trump abused his power when he asked Ukrainian President Volodymyr Zelenskiy to investigate former Vice President Joe Biden and his son Hunter Biden in a July 25 phone call.

On Thursday, Trump used a closed-door gathering with U.S. diplomats in New York to attack the elder Biden and disparage a whistle-blower complaint, according to a video obtained by Bloomberg News.

“We’re at war,” Trump said at the event on Thursday. “I want to know who’s the person, who’s the person who gave the whistle-blower the information? Because that’s close to a spy.”

Pelosi said she’s hopeful that lawmakers in Congress can put political divisions aside.“At this time Democrats and Republicans would have to put country before party,” she said.

To contact the reporters on this story: Billy House in Washington at bhouse5@bloomberg.net;Caitlin Webber in Washington at cwebber4@bloomberg.net

To contact the editors responsible for this story: Joe Sobczyk at jsobczyk@bloomberg.net, Elizabeth Wasserman, Ros Krasny

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