In this file photo taken on September 26, 2019 US Speaker of the House Nancy Pelosi talks during her weekly press briefing on Capitol Hill in Washington, DC. Picture: ANDREW CABALLERO-REYNOLDS / AFP
In this file photo taken on September 26, 2019 US Speaker of the House Nancy Pelosi talks during her weekly press briefing on Capitol Hill in Washington, DC. Picture: ANDREW CABALLERO-REYNOLDS / AFP

Washington — The Democratic Party-led US House of Representatives was set on Wednesday to push forward with its impeachment investigation of President Donald Trump over his dealings with Ukraine, a day after the White House declared its refusal to co-operate with the probe.

The three congressional committees leading the inquiry were working on final arrangements to interview a US intelligence officer who filed the whistle-blower complaint that triggered the probe, a day after the state department abruptly blocked the US ambassador to the EU from speaking to them.

The investigation is focused on whether Trump used almost $400m in congressionally approved aid to Ukraine as leverage to pressure the Ukrainian president to launch an investigation into former vice-president Joe Biden, one of Trump’s main Democratic rivals as he seeks re-election in 2020.

Trump has denied wrongdoing and defended a July 25 phone call to Ukrainian President Volodymyr Zelensky, in which he pressed Zelensky to investigate Biden and his son who sat on the board of a Ukrainian firm.

White House counsel Pat Cipolline on Tuesday told house speaker Nancy Pelosi and other top Democrats that the administration would refuse to co-operate with what it called an “illegitimate” and “unconstitutional” impeachment inquiry.

“The effort to impeach President Trump ... is a naked political strategy that began the day he was inaugurated,” Cipolline wrote in an 8-page letter.

Pelosi, in response, said: “Mr President, you are not above the law. You will be held accountable.” She did not indicate what steps, if any, house Democrats might take to compel Trump’s co-operation.

In addition to the whistle-blower, lawmakers aim to hear later this week from a former US ambassador to Ukraine, Marie Yovanovitch, whom Trump removed from that post last May before her term was up. Lawyers for the whistle-blower were focused on how to protect the person’s identity from being made public during any testimony, according to sources close to the talks.

Trump has repeatedly criticised the probe and the Democrats leading it, and called for the whistle-blower to be exposed. Several of his Republican allies in the house on Tuesday backed unmasking the person’s identity but said they would not do it.

“The whistle-blower and others spoke BEFORE seeing the transcript. Now they must apologise to me and stop this ridiculous impeachment,” he tweeted on Wednesday, referring to a White House readout of the July call.

The showdown between Trump and Pelosi heightened just as a newly released Reuters/Ipsos opinion poll showed Democratic support rising for impeachment. Among all adult Americans, 45 % support impeachment while 39 % oppose it, according to the poll, unchanged from last week.

Relations raw 

Relations between Democrats and Republicans in Congress were already raw when the state department on Tuesday ordered US ambassador to the EU Gordon Sondland, a major Trump political donor, not to appear at a closed-door meeting of three US house panels investigating Trump.

Democrats view Sondland as a key witness who could help shed light on whether Trump withheld military aid to Ukraine as part of an effort to pressure it to investigate Biden and his son. Trump has alleged corruption by the Bidens, but has not provided any evidence to back that up.

The move prompted Democrats to accuse Trump of obstructing their investigation and Republicans to accuse Democrats of operating a secretive, biased inquiry.

The hot rhetoric in the high-stakes battle between Trump and Democrats, who control the House is expected to intensify next week when Congress returns from a two-week recess.

On their return, members will huddle privately to discuss strategy if Pelosi decides in coming weeks or months to go ahead with articles of impeachment against Trump.

Republican Senate majority leader Mitch McConnell has said he would have no choice but to initiate a Senate trial on whether to convict Trump of any formal charges of “high crimes or misdemeanours” lodged by the house.

But he added in an interview with CNBC: “How long you’re on it, is a whole different matter,” possibly referring to the right of any senator to move to dismiss the charges, thus short-circuiting a full-blown Senate trial and a vote on convicting Trump — if the motion were to be approved.

Republicans who control the Senate have shown little appetite for ousting Trump.

Lindsey Graham on Wednesday told Fox News he would push fellow Senate Republicans to send Pelosi a letter saying that the White House’s readout of Trump’s call with Zelensky did not show an impeachable offence “so she can stop” the proceedings.