Donald Trump pushed the United States towards a constitutional crisis on Tuesday when his legal counsel said the White House would refuse to cooperate with Congress’s impeachment inquiry.

“Given that your inquiry lacks any legitimate constitutional foundation, any pretense of fairness, or even the most elementary due process protections, the Executive Branch cannot be expected to participate in it,” the counsel Pat Cipollone said in a letter to Democratic leaders in the House of Representatives.

The eight-page missive came after the Trump administration abruptly blocked a key witness in the Ukraine scandal from appearing before the congressional impeachment inquiry and sets up a clash between the White House and Congress – the executive and legislative branches – in the weeks ahead.

The letter appeared to put the emphasis on political rebuttal rather than structured legal argument – perhaps marking a new strategy to counter the impeachment threat with stalling and counter-attacking.

Trump aides have begun honing their approach after two weeks of what some allies have described as a listless and unfocused response to the inquiry.

The inquiry was launched by the House speaker, Nancy Pelosi, last month after it emerged that, in a July phone call, Trump had pressed the leader of Ukraine to investigate a political rival, Joe Biden. The president and his allies have sought to question the inquiry’s legitimacy.

In particular, the White House objects that the House did not formally vote to begin the impeachment inquiry, breaking with precedent set in the inquiries into Richard Nixon and Bill Clinton.

Pelosi has insisted the House is well within its rules to conduct oversight of the executive branch under the constitution regardless of a vote.

Refuse, block, stonewall – but Trump's strategy leaves little margin for error Read more

The administration is also sharply critical of the conduct of House intelligence committee chairman, Adam Schiff, whose committee is leading the inquiry, and it appears determined to stonewall Democrats for as long as possible.

In its most aggressive response yet, Cipollone wrote in the letter, released in the late afternoon on Tuesday: “Your unprecedented actions have left the president with no choice. 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 cannot participate in your partisan and unconstitutional inquiry under these circumstances.”

Cipollone’s letter threatens to end cooperation with Congress on important oversight matters, accusing members of formulating their investigation “in a manner that violates fundamental fairness and constitutionally mandated due process”.

It adds: “To comply with the Constitution’s demands, appropriate procedures would include – at a minimum – the right to see all evidence, to present evidence, to call witnesses, to have counsel present at all hearings, to cross-examine all witnesses, to make objections relating to the examination of witnesses or the admissibility of testimony and evidence, and to respond to evidence and testimony.”

In a statement responding to the letter, Pelosi said: “The White House letter is only the latest attempt to cover up his betrayal of our democracy, and to insist that the President is above the law. The letter is manifestly wrong, and is simply another unlawful attempt to hide the facts of the Trump Administration’s brazen efforts to pressure foreign powers to intervene in the 2020 elections.”

Earlier, the state department said the US ambassador to the European Union, Gordon Sondland, a Trump political donor, would not be allowed to appear, even though he had already travelled from Europe to testify behind closed doors. Trump decried the Democratic-led inquiry into whether he abused his office in the pursuit of personal political gain as a “kangaroo court”.

Q&A How do you impeach the US president? Show Hide Article 1 of the United States constitution gives the House of Representatives the sole power to initiate impeachment and the Senate the sole power to try impeachments of the president. A president can be impeached if they are judged to have committed "treason, bribery, or other high crimes and misdemeanors" – although the US Constitution does not specify what “high crimes and misdemeanors” are.

The formal process starts with the House of Representatives passing articles of impeachment, the equivalent of congressional charges. According to arcane Senate rules, after the House notifies the Senate that impeachment managers have been selected, the secretary of the Senate, Julie Adams, tells the House that the Senate is ready to receive the articles. Then impeachment managers appear before the Senate to “exhibit” the articles, and the Senate confirms it will consider the case. The presiding officer of the Senate notifies the supreme court chief justice, John Roberts, of the impending trial. Roberts arrives in the Senate to administer an oath to members. The presiding officer will then administer this oath to senators: “I solemnly swear that in all things appertaining to the trial of the impeachment of Donald Trump, now pending, I will do impartial justice according to the constitution and laws, so help me God.” The Senate must vote on a resolution laying out ground rules for the trial including who the key players will be, how long they will get to present their cases and other matters. After the Senate is “organized”, the rules decree, “a writ of summons shall issue to the person impeached, reciting said articles, and notifying him to appear before the Senate upon a day and at a place to be fixed by the Senate”. A president has never appeared at his own impeachment trial. Trump will be represented by the White House counsel, Pat Cipollone, and his personal lawyer Jay Sekulow, among others. After the oath, the trial proper will begin. Senators may not speak during the proceedings but may submit written questions. The question of witnesses and other matters would be decided on the fly by majority vote. A time limit for the proceedings will be established in the initial Senate vote. The senators will then deliberate on the case. In the past this has happened behind closed doors and out of public view. The senators vote separately on the two articles of impeachment – the first charging Trump with abuse of power, the second charging him with obstruction of Congress. A two-thirds majority of present senators – 67 ayes if everyone votes – on either article would be enough to convict Trump and remove him from office. But that would require about 20 Republicans defections and is unlikely. The more likely outcome is a Trump acquittal, at which point the process is concluded. Two presidents have previously been impeached, Bill Clinton in 1998, and Andrew Johnson in 1868, though neither was removed from office as a result. Richard Nixon resigned in 1974 before there was a formal vote to impeach him. Tom McCarthy in New York

Democrats condemned the move, calling it an attempt to obstruct their inquiry, and issued a subpoena for Sondland, seeking documents by 14 October and a deposition on 16 October.

Schiff said the ambassador’s no-show was “yet additional strong evidence” of obstruction of Congress by Trump and the secretary of state, Mike Pompeo, that will only strengthen a possible impeachment case.

Meanwhile, Trump’s personal lawyer, Rudy Giuliani, has said he will not testify before the House intelligence committee unless committee members vote to remove Schiff. “I wouldn’t testify in front of that committee until there is a vote of Congress and he is removed,” Giuliani told the Washington Post. “Let them hold me in contempt. We’ll go to court. We’ll challenge the contempt.”

He added: “The position I’m stating is now the position of the administration.”

The House committees leading the fast-moving investigation intend to call and subpoena a number of Trump administration witnesses. The investigation could lead to the approval of articles of impeachment against Trump in the House. A trial on whether to remove him from office would then be held in the Senate, where Republicans have the upper hand.

Trump’s supporters in the House endorsed the letter. The House Republican leader, Kevin McCarthy, said: “House Democrats have wanted to undo the results of the 2016 election for three years, and now they’re rushing a sham impeachment process.



“President Trump is right to call out this rushed process because Democrats refuse to protect the transparency and basic fairness that have been integral to previous impeachment proceedings.”

The Associated Press contributed to this report