Rudy Giuliani

Giuliani accuses former US ambassador Yovanovitch of blocking efforts to persuade Ukraine to investigate the Bidens

Trump wanted Kiev to investigate Hunter Biden's activities in Ukrainian gas firm Burisma

The scandal has now ensnared Sondland, who agreed to be deposed by House Democrats probing the matter

A potential second whistleblower was reportedly weighing whether to come forward

Those largely unsubstantiated allegations have ensnared allies in Britain, Italy and Australia

The whistleblower, who could testify soon before Congress, fears for their safety if their identity is revealed

Officials deny the renewed email effort has any political motivation

Any whistleblower must signal his or her complaint to the inspector general, who has 14 days to review it

Public support is growing for impeachment after the release of an anonymous whistleblower's complaint on Thursday

The White House on Wednesday put out a summary of a July 25 call with Ukraine's newly elected president

A more defiant Trump has earlier insisted he exerted no pressure on Kiev

He denies that he has abused his office

He says he has frozen hundreds of millions of dollars in aid to Ukraine

He is Trump’s main man to seek dirt from Ukraine on his potential 2020 Democratic opponent Joe Biden

President Trump’s lawyer believes that when enough people issue threats against sovereign nations, they are legal

Secret $130,000 payment was made on the eve the hotly contested 2016 US presidential election

Giuliani was an early supporter of Trump, has been his friend for many years and has defended him vigorously