House impeachment managers delivered opening remarks during the US Senate trial into Donald Trump and his dealings with Ukraine, as Democrats blasted White House attorneys for presenting Fox News-style “histrionics" at the hearings.

Democratic impeachment manager Adam Schiff ​argued in his opening remarks the president's "misconduct cannot be decided at the ballot box" and suggested that Americans "cannot be assured that the vote will be fairly won" in 2020 after Mr Trump encouraged Ukraine to launch political investigations into one of his Democratic rivals, Joe Biden.​

House Judiciary Chairman Jerrold Nadler, another impeachment manager, also accused Republicans of “voting for a cover-up”, observing: “Only guilty people hide the evidence.”

The prosecution's marathon opening statements included clips from witness testimonies and, most damning, from the president himself, including his admission that he would accept politically damaging information on a rival candidate from a foreign country and would ask China to investigate the Bidens.

House impeachment managers, acting as the prosecution, each handled a different aspect of the charges against the president and the players involved, from Rudy Giuliani's influence and direction under the president to pressure Ukraine into an investigation, to the on-the-ground consequences of withholding military aid to Ukraine while it was in the middle of a ground war with Russia.

Looking on from the World Economic Forum in Davos, Switzerland, the president fired out dozens of retweets in support of his cause while insisting he was “making great progress” at the global summit, as a new poll makes bleak reading for his supporters ahead of 2020.

The president appeared to acknowledge his administrations' participation in the obstruction charges against him by telling reporters: "Honestly, we have all the material. They don't have the material."

He also falsely claimed that Democrats leading his impeachment "don't talk about my conversation" with Ukrainian president Volodymyr Zelenksky and that "they don't talk about my transcripts" that the president believes exonerate him.