A letter sent to Democratic leaders rejected it as "baseless" and "constitutionally invalid".
For his part, Giuliani, the president's lawyer who has been subpoenaed for documents, said the Democrats would "make fools out of themselves" if they tried to hold him or others in contempt. Giuliani also echoed criticism of the inquiry, which he compared to the midcentury Red Scare by dubbing it "worse than Joe McCarthy".
The letter comes the same day that Trump intensified his fight with Congress by blocking Gordon Sondland, the U.S. European Union ambassador, from testifying behind closed doors about the president's dealings with Ukraine.
What does the letter say?
Cipollone's letter, which was addressed to House Speaker Nancy Pelosi and the chairmen of the three committees, argued the inquiry is partisan and a violation of due process.
In slightly more measured terms, the letter asks Democrats to drop the entire process.
"In order to fulfil his duties to the American people. In order to fulfill his duties to the American people, the Constitution, the Executive Branch, and all future occupants of the Office of the Presidency, President Trump and his administration can not participate in your partisan and unconstitutional inquiry under these circumstances", it read.
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Schiff, commenting before the White House letter was released, said, "For this impeachment inquiry we are determined to find answers".
In a phone call with Yahoo News, Jay Sekulow, another one of Trump's attorneys, suggested the decision to block Sondland from testifying could be the beginning of a larger showdown, with other officials not complying with requests for testimony or documents.
The lawyer for the first intelligence whistleblower who came forward with accusations concerning President Donald Trump and his interactions with Ukraine said Sunday he is representing a second whistleblower regarding the President's actions. It also claims that Trump's due process rights are being violated and is attacking the conduct of House intelligence committee Chairman Adam Schiff.
"It is completely normal for the State Department to vet these messages before providing the copies to Congress", said the official.
"The failure to produce this witness", the California Democrat added, "the failure to produce these documents, we consider yet additional strong evidence of obstruction of the constitutional functions of Congress". 56 percent of the USA public now disapproves of the way Republicans are responding to the impeachment inquiry, while 33 percent approve.
The Democratic-led inquiry is seeking to find out if the president withheld almost $US400m in aid to pressure Ukraine's President Volodymyr Zelensky to set up an inquiry into Mr Biden.
These claims have been widely discredited.
The existence of the 2d whistleblower followed stirrings of discontent inner Trump's grasp Republican Party after he called on China on Friday to match Biden's son, who had industry dealings in China. This has raised concerns that the whistleblower's identity could be leaked by those in the investigation's orbit who would typically have unaltered access to the testimony.