But Nunes has pressed forward with efforts to question the whistleblower publicly by including the unnamed individual on a list of witnesses House Republicans would like the opportunity to hear from once public hearings in the impeachment inquiry begin on Wednesday.
Trump has accused the Bidens of unspecified corruption due to Hunter Biden's role as a director of Ukraine energy company Burisma when Joe Biden - now a leading candidate to challenge Trump in the 2020 election - was vice president.
House Republicans released their request for witnesses on Saturday, including Hunter Biden, the son of former Vice President Joe Biden, an individual referred to as "the anonymous whistleblower, "senior diplomat Kurt Volker, Tim Morrison, the senior director for Europe and Russian Federation on the White House National Security Council, and Under Secretary of State for Political Affairs David Hale".
"Your failure to fulfill Minority witness requests shall constitute evidence of your denial of fundamental fairness and due process", said the California Republican in his Saturday letter.
State Department official George Kent, who testified behind closed doors before committees, told congressional investigators that he raised concerns about Hunter Biden's role one the board of Burisma Holdings in 2015, but was rejected by Joe Biden's staff.
As violence hits Hong Kong, its shares lead a decline across Asia
About 5.5 billion shares changed hands in USA exchanges, below the 6.8 billion-share daily average over the last 20 sessions. In Europe, Germany's DAX fell 0.4 per cent to 13,176 while the CAC 40 in France was down 0.1 per cent at 5,884.
House Republicans are on the offensive demanding Hunter Biden and the Ukrainian phone call whistleblower to testify for the impeachment inquiry. "So if they don't call the whistleblower in the House, this thing is dead on arrival in the Senate".
Snubbing House subpoenas, the White House, citing Trump's executive privilege, blocked his top aides from testifying, and has withheld documents related to Ukraine policy.
But Speier said the whistleblower, whose identity is protected, isn't needed, and any testimony has to be focused on the July call in which Trump asked Ukrainian President Volodymyr Zelenskiy to investigate the Bidens. Trump has denied any wrongdoing.
"This is not about Schiff finding the truth, this is about Schiff trying to destroy the Trump presidency", Graham said.
Speier argued that having Hunter Biden testify would also be "irrelevant" because he "is unrelated to the Ukraine call".
Trump has pushed an unproven accusation that then-Vice President Biden improperly tried to help his son by pressuring the Ukrainian government to fire the country's prosecutor general.
Chicago & Denver flights canceled at Hector International Airport
The jetliner was carrying 41 passengers and crew and none were injured in the incident, American Airlines said in a statement. Chicago is expected to experience up to six inches of snow in the next 24 hours as a Winter Weather Advisory is in place.
This week's public hearings will start Wednesday with testimony from two diplomats: William Taylor, the acting US ambassador to Ukraine, and George Kent, the deputy assistant Secretary of State for European and Eurasian affairs.
"I think we've gotten lost in this whole idea of quid pro quo", Paul said, using the Latin phrase meaning "something for something", which describes a service or favor being expected in return for one provided.
The President has been encouraging media outlets to out the whistleblower, and he wrote in a September tweet that "Like every American, I deserve to meet my accuser".
However, Trump and/or his lawyer would be allowed to attend later hearings before the House judiciary committee, which will debate what, if any, articles of impeachment should be filed and sent to the floor for a vote.
SpaceX successfully launches Falcon 9 rocket with 60 satellites on board
A Falcon-9 rocket launched from Cape Canaveral, Florida, placed 60 mini-satellites in orbit, joining 60 others launched in May. Starlink satellites use Krypton-fueled electric thrusters to reach their target orbit after leaving their rocket .