WASHINGTON, Oct. 2 (Xinhua) -- U.S. House Speaker Nancy Pelosi said Wednesday that her chamber had "no choice but to go forward" with the impeachment proceedings against President Donald Trump over his controversial interactions with Ukraine.
"We see the actions of this President being an assault on the Constitution," Pelosi told a news conference.
"We had no choice but to go forward. It's hard. We want to weigh the equities. We want to be fair as we go forward," said the Democratic congresswoman, who was joined by House Intelligence Committee Chairman Adam Schiff.
The impeachment inquiry, announced by Pelosi on Sept. 24, stemmed from a whistleblower complaint alleging that Trump pressured Ukrainian President Volodymyr Zelensky during a July 25 phone call to investigate Joe Biden, Democratic presidential candidate for the 2020 election, as well as issues related to alleged Russian interference in the 2016 election.
Schiff, Democratic House representative representing California, accused the White House of attempting to "stonewall" the ongoing investigations into the Trump-Ukraine controversy conducted by six House committees.
"We are concerned that the White House will attempt to stonewall our investigation much as they have stonewalled other committees in the past," Schiff said at the news conference.
"The White House needs to understand that any action like that, that forces us to litigate or have to consider litigation will be considered further evidence of obstruction of justice," he added.
Pelosi said she hoped that Democrats will be able to work with Trump to advance legislation on lowering prescription drug prices as well as the U.S.-Mexico-Canada trade agreement, even as the impeachment process continues.
"So, when the President says he can't do anything if he has the threat of impeachment or the consideration of impeachment, I hope he doesn't mean he doesn't want to work together," Pelosi said.
Trump, who has been defending himself throughout the process so far and who appeared to be watching the Pelosi-Schiff news conference, tweeted that Pelosi "is incapable of working on either" of the legislation she mentioned.
"It is just camouflage for trying to win an election through impeachment." the president added.
In a separate tweet, Trump said Schiff "completely fabricated my words (with Zelensky) and read them to Congress as though they were said by me."
Three House committees, Intelligence, Foreign Affairs and Oversight and Reform, have subpoenaed Secretary of State Mike Pompeo and Rudy Giuliani, Trump's personal attorney who the whistleblower complaint claimed has been a central figure in the administration's dealings with Ukraine. The two were asked to submit related documents.
Oversight and Reform Committee Chairman Elijah Cummings in a memo notified committee members Wednesday that the panel, in consultation with the Intelligence and Foreign Affairs committees, will issue a subpoena to the White House on Friday, requesting Ukraine-related records.
"The White House's flagrant disregard of multiple voluntary requests for documents-combined with stark and urgent warnings from the Inspector General about the gravity of these allegations - have left us with no choice but to issue this subpoena," read the memo.