US President Donald Trump speaks during a ceremony.
WASHINGTON - Donald Trump's conduct with Ukraine was far worse than the behavior that led to Richard Nixon's downfall, the head of the congressional impeachment probe said on Thursday as he summed up the case for the US president's removal.
Lawmakers investigating whether Trump abused his office by bullying Ukraine into assisting his reelection efforts have spent three days hearing the most explosive witness testimony since the scandal broke.
Democrats accuse Trump of demanding Ukraine's assistance in a July 25 phone call and via a circle of accomplices, mainly senior figures in his administration.
He stalled almost $400-million in military aid and a White House visit for new Ukrainian president Volodymyr Zelensky, allegedly to coerce Kiev - which is at war with Russia - into helping.
The plot would have worked, say Democrats, if not for a whistleblower whose complaint about the July call reached Congress on September 9, ensuring the aid was handed over two days later.
"What we've seen here is far more serious than a third-rate burglary of the Democratic headquarters," said House Intelligence Committee Chairman Adam Schiff, referring to the infamous 1972 Watergate break-in that Nixon ordered, eventually leading to his resignation.
"What we're talking about here is the withholding of recognition in that White House meeting (and) the withholding of military aid to an ally at war. This is beyond anything Nixon did."
Schiff spoke at the close of marathon testimony by nine witnesses over three days - on top of two days of hearings last week - that produced an avalanche of corroboration for the allegations against Trump.
Democrats are expected to prepare formal articles accusing Trump of abusing his presidential powers, bribery and obstruction of justice.
The investigation threatens to make him the third US president to be impeached, although the Republican-controlled Senate would need to convict him to remove him from office.
In bombshell testimony Wednesday, Washington's envoy to the European Union testified that Trump tied the White House meeting to the investigation of Democratic 2020 frontrunner Joe Biden.
Ambassador Gordon Sondland told the panel Trump ordered him and other diplomats to answer to the president's personal lawyer Rudy Giuliani, a private citizen with no public office, on Ukraine policy.
The former Soviet state, Democrats have noted, is not in the European Union.
Giuliani's demands to Ukraine for investigations, Sondland said, "were a quid pro quo for arranging a White House visit for President Zelensky."
On Thursday a former top White House Russia expert publicly rejected a Kremlin conspiracy theory pushed by Trump and his Republican allies that Ukraine helped the Democrats in the 2016 election.
The supposed plot, which Trump also asked Zelensky to investigate, was designed to stir havoc in US politics, said Fiona Hill, a senior official on Trump's National Security Council until July.
"This is a fictional narrative that has been perpetrated and propagated by the Russian security services themselves," she told lawmakers.
"These fictions are harmful even if they are deployed for purely domestic political purposes."
Hill testified that she and other specialists involved in Ukraine policy were unnerved by the efforts of Trump, Giuliani and Sondland between March and September to pressure Ukraine.
Sondland, she told the House Intelligence Committee, "was involved in a domestic political errand" at odds with her team's focus on US national security policy toward Ukraine.
"What we were trying to do was block him from straying into domestic politics," she said.
"I said to him... I think this is all going to blow up. And here we are," she told the panel.
Trump backers in Congress and the media have increasingly struggled to defend the president, mostly complaining about the process and impugning the motives of a roll call of nonpartisan witnesses rather than offering evidence to counter the accusations against him.
"What is happening is not good for our culture, not good for our nation, and yet the Democrats do not care," said Republican Representative Jim Jordan.
"The facts are on the president's side. The truth is on the president's side."
White House spokesman Hogan Gidley in a statement urged Democrats to drop the probe, while saying "President Trump wants to have a trial in the Senate because it's clearly the only chamber where he can expect fairness and receive due process under the Constitution."
But Schiff delivered a powerful argument at the conclusion of the hearings Thursday that Trump believed he was "beyond accountability."
"And in my view there is nothing more dangerous than an unethical president who believes they are above the law," Schiff said.