Washington (AFP) - Democratic efforts to introduce new witnesses at US President Donald Trump's impeachment trial were dealt a likely fatal blow on Friday when a key Republican senator said she would not support the move.
Senator Lisa Murkowski of Alaska said she would vote "no" when the motion to call further witnesses is considered by the Senate later Friday.
Republicans hold a 53 to 47 seat edge in the Senate and four Republicans needed to side with the Democrats for new witnesses to be introduced.
Murkowski had been considered one of only a handful of Republicans who might support the motion.
But the senator from Alaska said the articles of impeachment passed by the Democratic-controlled House of Representatives were "rushed and flawed."
"I carefully considered the need for additional witnesses and documents, to cure the shortcomings of the process, but ultimately decided that I will vote against considering motions to subpoena (witnesses)," she said in a statement.
Murkowski's decision could pave the way for Republican Senate Majority Leader Mitch McConnell, a Trump ally, to call for a vote to acquit the president, potentially as early as Friday night.
Democrats were particularly eager to hear from former national security advisor John Bolton, who reportedly claims in an upcoming book that Trump personally told him that military assistance to Ukraine was tied to Kiev investigating his Democratic rival Joe Biden.
The charge is at the heart of the House of Representatives' December 18 impeachment of the 45th US president for abuse of power and obstruction of Congress.
