WASHINGTON (Reuters) - Democratic U.S. lawmakers have begun the next step in the impeachment inquiry into President Donald Trump - writing a report on their findings - but still could take more testimony and hold additional hearings, the chairman of the House of Representatives Intelligence Committee said on Sunday.

Representative Adam Schiff, whose committee is leading the inquiry that threatens Trump’s presidency, said the panel has started work on the report after two weeks of public hearings with testimony from current and former U.S. officials. The panel has held five public hearings and has no more scheduled.

The report is an important step toward a possible vote in the Democratic-led House on articles of impeachment - formal charges - against the Republican president. If those are approved, the Senate, controlled by Republicans, would then hold a trial on whether to convict Trump and remove him from office. Republicans have shown little inclination toward removing Trump, who is seeking re-election in 2020.

The inquiry centers on a July 25 phone call in which Trump asked Ukrainian President Volodymyr Zelenskiy to investigate political rival Joe Biden and his son Hunter Biden as well as a discredited conspiracy theory promoted by Trump that Ukraine, not Russia, interfered in the 2016 U.S. presidential election. Hunter Biden had worked for Burisma, a Ukrainian energy company.

“We don’t foreclose the possibility of more depositions, more hearings. We are in the process of getting more documents all the time. So that investigative work is being done,” Schiff said on CNN’s “State of the Union.”

“What we’re not prepared to do is wait months and months while the administration plays a game of ‘rope a dope’ in an effort to try to stall. We’re not willing to go down that road.” Schiff said.

Democrats have accused Trump of abusing his power by pressuring a vulnerable U.S. ally to interfere in an American election by digging up dirt on his domestic political opponents. Biden is a leading contender for the Democratic nomination to face Trump in the November 2020 election.

With the first party nominating contests set for February, “there’s an urgency to make sure the election and the ballot box have integrity,” Democratic Representative Eric Swalwell, an Intelligence Committee member, told the “Fox News Sunday” program.

Trump’s administration has refused to provide documents requested by House Democrats and blocked witnesses from testifying, including Secretary of State Mike Pompeo, former national security adviser John Bolton and acting White House Chief of Staff Mick Mulvaney. The president’s personal lawyer, Rudy Giuliani, also has refused to cooperate.

Bolton and other officials have sought court rulings on whether they should comply with a congressional subpoena or honor the Trump administration’s order not to testify, a process that could take months.

REPUBLICANS DEFEND TRUMP

Trump has said he did nothing wrong and dismisses the inquiry as politically motivated. Many Republicans in Congress have rallied to his defense and assailed the Democrats leading the inquiry.

There were “no impeachable offenses” and no direct evidence against the president, Representative Elise Stefanik, a Republican Intelligence Committee member, told the Fox News program “Sunday Morning Futures.”

FILE PHOTO - House Intelligence Committee Chairman Adam Schiff, D-Calif., questions Ambassador Kurt Volker, former special envoy to Ukraine, and Tim Morrison, a former official at the National Security Council, as they testify before the House Intelligence Committee on Capitol Hill in Washington, Tuesday, Nov. 19, 2019, during a public impeachment hearing of President Donald Trump's efforts to tie U.S. aid for Ukraine to investigations of his political opponents. Jacquelyn Martin/Pool via REUTERS

Schiff said the committee is learning more every day but the evidence already collected is so “overwhelming and uncontested” that Democratic lawmakers decided to begin writing a report on the findings for transmission to the House Judiciary Committee, which would draft any articles of impeachment.

“Even as we compile this report, even as we submit evidence to the Judiciary Committee, we’re going to continue our investigation,” Schiff said on NBC’s “Meet the Press” program.

The Judiciary Committee could conduct more proceedings if needed, including hearings, that allow Trump and his counsel to participate. The panel would draft any articles of impeachment against Trump before they would go to the full House for a vote.

Democrats also are looking into whether Trump’s decision to withhold $391 million in security aid to Ukraine was intended to pressure Kiev into conducting the two investigations that could benefit Trump politically.

The money - approved by the U.S. Congress to help Ukraine combat Russia-backed separatists in the eastern part of the country - was later provided to Kiev in September after the controversy had spilled into public view.

Schiff said his committee has been in touch with federal prosecutors in Manhattan about the possibility of getting witness testimony from Lev Parnas, an indicted Ukrainian-American businessman who has ties to Giuliani.

Parnas, who has already been subpoenaed for documents, had worked with Giuliani at a time when Trump’s lawyer was pushing for Ukraine to conduct the two investigations. A lawyer for Parnas has said he would comply with the document request and is willing to appear before the House panel.