Trump impeachment probe goes public

The impeachment inquiry into US President Donald Trump was set to reach a critical juncture yesterday when lawmakers launch their first televised public hearings, marking a new, high-stakes phase of proceedings that could determine the fate of his tumultuous presidency.

Democrats leading the US House of Representatives probe have summoned three US diplomats – all of whom have previously expressed alarm in closed-door testimony about Trump's dealings with Ukraine - to detail their concerns this week under the glare of wall-to-wall news coverage.

Though no president has ever been removed from office by impeachment, that has not deterred Democrats, who are looking into whether Trump abused his power by withholding nearly $400 million in security assistance to Ukraine to pressure the vulnerable US ally.

The focus is a July 25 phone call, in which Trump asked Ukrainian President Volodymyr Zelenskiy to open a corruption investigation into Biden and his son and into a discredited theory that Ukraine may have meddled in the 2016 US elections.

With a potential television audience of tens of millions, two witnesses – William Taylor, top US diplomat in Ukraine, and Deputy Assistant Secretary of State George Kent – will be sworn in before the House Intelligence Committee.