President Trump, says Taylor, "had a feeling of having been wronged by the Ukrainians and so this [investigation into the Bidens] was something that he thought they owed him to fix that wrong."

It's unclear why Trump reportedly disliked the Ukrainians, but some pundits speculate it could be linked to the so-called CrowdStrike conspiracy theory which holds it was Ukraine - not Russia - that meddled in the 2016 election.

This widely debunked theory was mentioned by Trump in his July call with Zelensky.

Did Sondland have a direct line of communication into president Trump? Taylor says yes.

The counsel asks: "Even though President Trump was saying repeatedly that there is no quid pro quo, Sondland relayed to you that the facts of the matter were that the White House meeting and security assistance were conditioned on the announcement of these investigations?"

Taylor agrees that was indeed his understanding.

Offering some new information from his closed-door testimony last month, Bill Taylor says a member of his staff overheard a conversation between Trump and Gordan Sondland, during which the "the investigations" came up.

When the aide asked what President Trump thought about Ukraine, Sondland replied that Trump "cares more about the investigations of Biden".

BBC's Anthony Zurcher calls the disclosure "explosive evidence of a connection between Trump and Sondland".

Image source, ALEX BRANDON/AFP via Getty Images

Now answering questions from the Democrat's counsel, Daniel Goldman, Taylor says that withholding military assistance "for no good reason" was "counterproductive".

"It could not be explained, it was crazy."

After his opening statement, Taylor answers questions. He tells committee members: "If we withdraw or suspend or threaten to withdraw our security assistance" to Ukraine, it sends a "message to Ukrainians, but its just as important to the Russians who are looking for any sign of weakness".

"That affects us" he adds. It affects the world that we live in; that our children and grandchildren will grow up in," he adds, appearing to become emotional.

"Ukraine is on the front line of that conflict," he concludes.

President Trump's 2020 re-election campaign is just out with a new pitch to supporters.

"The Democrats are playing a sick game," the campaign email begins.

"The Impeachment Scam hearings begin today! This is a compete Fake Hearing (trial) to interview Never Trumpers and a Pelosi-Schiff SCAM against the Republican Party and me," writes Trump.

The email ends with a plea to raise $3m (£2.4m) for his campaign in the next 24 hours.

Image source, Drew Angerer/Getty Images

Taylor concludes his opening statement by telling lawmakers there are two Ukraine stories before them.

The first "is a rancorous story about whistleblowers, Mr Giuliani, side channels, quid pro quos, corruption, and interference in elections".

"In this story, Ukraine is merely an object. But there is another Ukraine story - a positive, bipartisan one. In this second story, Ukraine is the subject...

"This one is about young people in a young nation, struggling to break free of its past... This story describes a nation developing an inclusive, democratic nationalism, not unlike what we in America, in our best moments."

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Image source, MSNBC via @DanielleMisiak

Image source, Fox via @DanielleMisiak

The country is divided on whether Trump should be impeached - and so is its media.

The conservative Fox News network calls Ambassador Bill Taylor a "never Trumper", and quotes the White House's accusations of "triple hearsay".

Liberal-leaning MSNBC describes him as a "top US diplomat" who testified to a "clear understanding" of the Ukraine scandal.

Image source, Andrew CABALLERO-REYNOLDS / AFP

Taylor says US Ambassador to the EU Gordon Sondland told him he wanted to "make sure no-one was transcribing or monitoring as they added President Zelensky to the call" - a request Taylor called "odd".

Taylor says his concerns "deepened" in August when he was told the "president doesn't want to provide any assistance at all" to Ukraine .

Taylor told then-National Security Adviser John Bolton of his concerns, and Bolton recommended he relay his concerns to Secretary of State Mike Pompeo directly, which he did.

"It had still not occurred to me that the hold on security assistance could be related to the 'investigations' [into the Bidens and alleged interference in the US elections]. That, however, would change."

White House Spokeswoman Stephanie Grisham tells reporters that the president is not across today's hearing.

"He's in the Oval in meetings. Not watching. He's working," she said.

David Martosko of the Daily Mail notes that no US Marine is standing guard outside the White House West Wing, as is customary when the president is inside.

Taylor says that by mid-July it was clear to him that the meeting President Zelensky wanted with President Trump "was conditioned on the investigations of [Ukrainian gas company] Burisma and alleged Ukrainian interference in the 2016 US elections".

Taylor says after Trump and Zelensky had their phone conversation, he did not receive a readout of the call from the White House, despite being the acting ambassador and having a meeting scheduled with Zelensky the next day.

Taylor says that then-National Security Adviser John Bolton "opposed a call between President Zelenskyy and President Trump".

He adds: "The Ukrainians in the meetings were confused. Ambassador Bolton, in the regular Ukraine policy decision-making channel, wanted to talk about security, energy, and reform; Ambassador Sondland, a participant in the irregular channel, wanted to talk about the connection between a White House meeting and Ukrainian investigations."

Image source, JIM LO SCALZO/Getty Images

Taylor also says ex-Ambassador Marie Yovanovitch was sidelined by the White House.

"There appeared to be two channels of US policy-making: one regular and one highly irregular. As acting ambassador, I had authority over the regular, formal diplomatic processes."

"At the same time I encountered an irregular, informal channel of policy making," he continues, adding that it was "unaccountable to Congress".

That irregular channel was led by US officials Kurt Volker, Gordon Sondland, Rick Perry, Mick Mulvaney and Rudy Giuliani, he says.

Image source, Chip Somodevilla/Getty Images

Bill Taylor lays out his main points, getting into the history of US-Ukraine relations.

"Ukraine is a strategic partner of the United States... Ukraine is on the front line in the conflict with a newly aggressive Russia."

Taylor adds that "it is clearly in our national interest to deter further Russian aggression".

"And finally, as the committee is aware, I wrote that withholding security assistance in exchange for help with a domestic political campaign in the United States would be crazy. I believed that then and I believe it now."

Top diplomat Bill Taylor says: "I am not here to take one side or the other or to advocate for any particular outcome of these proceedings."

Taylor has served under Republican and Democratic administrations. He is a Vietnam veteran.

Kent goes on to say that from 2018 to 2019 he "became increasingly aware" of efforts by Giuliani and "his associates Lev Parnas and Igor Fruman, to run a campaign to smear" the US ambassador to Kyiv. Parnas and Fruman, who are Soviet-born US citizens, were arrested in Florida for campaign finance violations last month.

He said some Ukrainians, including former "corrupt" prosecutors, "were now peddling false information in order to exact revenge against those who had exposed their misconduct, including US diplomats, Ukrainian anti-corruption officials, and reform-minded civil society groups in Ukraine".

Image source, AFP/Getty Images