The first transcripts released on Monday from closed door impeachment depositions in Congress show the former U.S. Ambassador to Ukraine was tipped off by Ukrainian government officials about the behind the scenes activities of President Trump's personal lawyer Rudy Giuliani, as Marie Yovanovitch said Giuliani's goal was to have her ousted from her diplomatic post.

"I do not know Mr. Giuliani's motives for attacking me," Yovanovitch told investigators on October 11, as the former Ambassador said she first learned Giuliani was up to something in Ukraine in late 2018.

"I really wasn't sure what exactly was going on," she added, as Yovanovitch detailed how she was puzzled and alarmed by public criticism from Donald Trump, Jr., and even Fox News talk host Sean Hannity.

"(O)ne of the senior Ukrainian officials was very concerned, and told me I really needed to watch my back," the former ambassador added.

"I understand, everyone understands, that I served at the pleasure of the President, I was nevertheless incredulous that the U.S. Government chose to remove an ambassador based, as far as I can tell, on unfounded and false claims by people with clearly questionable motives," she said.

The two men from Florida named by the Ambassador - Lev Parnas and Igor Fruman - were arrested as they attempted to leave the United States in October, and subsequently charged with campaign finance violations.

Asked about criticism featured in the rough transcript of the phone call between President Trump and the Ukraine leader, Yovanovitch said she was worried by what she read in that White House document - as the President called her 'bad news.'

"I hate to be repetitive, but I was shocked," the Ambassador testified, as investigators pointed out where Mr. Trump said she was 'going to go through some things.'

"Did you feel threatened?" Yovanovitch was asked.

"Yes," she replied.

The other transcript released on Monday came from Michael McKinley, who recently resigned as a top aide to Secretary of State Mike Pompeo.

Two more transcripts will be released on Tuesday, from the former special U.S. envoy to Ukraine, Kurt Volker, and from the U.S. Ambassador to the European Union, Gordon Sondland.