US President Donald Trump has attacked the former US ambassador to Ukraine, Marie Yovanovitch, on Twitter, in the middle of her testimony to the impeachment inquiry.
"Everywhere Marie Yovanovitch went turned bad," Mr Trump wrote. "She started off in Somalia, how did that go?"
He said it was "a US President's absolute right" to appoint ambassadors.
Replying in real time, Ms Yovanovitch called it "very intimidating".
Her response – at the invitation of hearing chairman Adam Schiff – was broadcast live during the televised testimony.
Mr Schiff, the Democratic Chairman of the Intelligence Committee overseeing the impeachment inquiry, suggested the president's tweets could be classed as witness intimidation.
The inquiry is currently investigating whether Mr Trump withheld US military aid to Ukraine in order to pressure the country's new president to announce a corruption inquiry into former Vice President Joe Biden, now his rival for the US presidency.
Mr Trump denies any wrongdoing and has branded the proceedings "presidential harassment".
Ms Yovanovitch was removed as ambassador to Kyiv in May, two months before a controversial phone call between Mr Trump and his Ukrainian counterpart Volodymyr Zelensky, which is now key to the inquiry.
A rough transcript of the call revealed that Mr Trump had urged President Zelensky to investigate discredited allegations against Mr Biden and his son Hunter, who sat on the board of a Ukrainian gas company.
What else did Yovanovitch tell the inquiry?
Responding directly to the president's tweet in which he appeared to blame her for upheaval in Somalia, Ms Yovanovitch replied: "I don't think I have such powers, not in Mogadishu and Somalia and not in other places."
"I actually think that where I've served over the years I and others have demonstrably made things better, you know, for the US as well as for the countries that I've served in," she said.
In earlier closed-door testimony, Ms Yovanovitch alleged she had fallen victim to a smear campaign at the hands of Mr Trump's personal lawyer Rudy Giuliani.
She said Mr Giuliani had started working to discredit her while attempting to push Ukraine into the anti-Biden investigations.
On Friday, the former envoy accused the US state department – headed by Mike Pompeo – of failing to resist "foreign and corrupt interests" she said had "hijacked" America's policy towards Ukraine.
When Ms Yovanovitch left her post, she was replaced by Bill Taylor, the current acting ambassador to Ukraine.
On Thursday, Mr Taylor testified before the impeachment inquiry that a member of his staff had overheard a telephone call in which the president inquired about "the investigations" into Mr Biden.
Trump makes his presence felt
Donald Trump has boasted that his conduct while in office – blunt language and shoot-from-the-hip tweeting – is "modern-day presidential". If so, welcome to a modern-day presidential impeachment hearing.
Just over an hour into Marie Yovanovitch's testimony, Mr Trump launched the kind of Twitter fusillade that has become a regular part of his political repertoire. He questioned the ambassador's competence, noted that the Ukrainian president spoke unfavourably about her and pointed out that he has the right to fire diplomats at will.
What makes the moment historic is that Committee Chair Adam Schiff gave Yovanovitch a chance to refute the president's tweet almost iRead More – Source