Twenty years after leading the impeachment efforts against Bill Clinton, Ken Starr made his debut on the Senate floor in defence of Donald Trump, while two Republican senators admit that John Bolton's testimony is becoming "increasingly likely" following bombshell revelations in the former national security chief's book.
The president reacted angrily after the manuscript Mr Bolton's book was leaked in which the former aide claims the president told him the decision to withhold military assistance to Ukraine last summer was explicitly tied to demands for an investigation into Joe Biden.
"If John Bolton said this, it was only to sell a book," Mr Trump tweeted, arguing that the House should have subpoenaed Mr Bolton when it was gathering evidence in November (it did), prompting impeachment manager Adam Schiff to say the revelation "blasts another hole" in his counsel's defence.
Senator Mitt Romney said Mr Bolton's revelations are "relevant" and that he would like to hear them on the Senate floor.
Susan Collins of Maine echoed Mr Romney's concerns and said that Mr Bolton's claims "strengthen the case for witnesses and have prompted a number of conversations among my colleagues".
Mr Starr was widely criticised for his defence and accused of contradicting his own arguments he made as a prosecutor. He derided the impeachment of Mr Trump over a lack of bipartisan support and claimed that the president was afforded executive privilege allowing him to withhold documents and testimony from subpoenas.
The president's defence also attacked Joe Biden and his son Hunter for what they argued was his corrupt role on the board of Ukrainian energy company Burisma.
Meanwhile, Fox host Chris Wallace railed against a contributor he told to "get your facts straight" on air as the talking heads squabbled over the admission of evidence in the Clinton trial compared to the Trump proceedings.
The president intends to announce those plans on Tuesday amid widespread criticism and calls for boycotts from Palestinians, who have largely been ignored from US-led discussions over the region's future.
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