WASHINGTON — Gordon Sondland, the U.S. ambassador to the European Union, will testify next week to House committees leading the impeachment inquiry into President Donald Trump, defying the State Department's direction not to cooperate.

“Notwithstanding the State Department’s current direction to not testify, Ambassador Sondland will honor the Committees’ subpoena, and he looks forward to testifying on Thursday,” Sondland's attorneys, Robert Luskin and Kwame Manley, said in a statement Friday.

Sondland's joint deposition before the House Foreign Affairs, Intelligence and Oversight committees is scheduled for Oct. 17. Axios was first to report that Sondland would appear next week.

Sondland's closed-door interview was originally scheduled for this week, but his appearance was blocked by the Trump administration. In response, the Democratic chairmen of the House committeesissued a subpoena for Sondland, seeking both his testimony and documents they charge Secretary of State Mike Pompeo is withholding from Congress.

Sondland, a Trump political appointee, has emerged as a central player in Trump's bid to persuade Ukraine’s new government to commit publicly to investigate corruption and the president's political opponents.

Sondland, through his lawyers, said Friday that he would not share the documents demanded by the House committees, claiming that those records were property of the State Department.

"Federal law and State Department regulations prohibit him from producing documents concerning his official responsibilities. Ambassador Sondland does not control the disposition of his documents. By federal law and regulation, the State Department has sole authority to produce such documents, and Ambassador Sondland hopes the materials will be shared with the Committees in advance of his Thursday testimony,” Sondland's lawyers said in the statement.

Sondland, a hotelier and Republican megadonor, was nominated to be ambassador to the European Union one year after he made a $1 million donation to Trump's inaugural committee.

Sondland was named by Trump's personal attorney, Rudy Giuliani, as one of two senior U.S. diplomats Giuliani coordinated with on his efforts in Ukraine. The other diplomat, former Ukraine envoy Kurt Volker, resigned amid the chaos last month.

Text messages provided to Congress show Sondland and another ambassador worked to persuade Ukraine to publicly commit to investigating Trump’s political opponents and explicitly linked the inquiry to whether Ukrainian President Volodymyr Zelenskiy would be granted an official White House visit.

The messages, released this month by House Democrats, show the diplomats coordinating with both Giuliani and a top Zelenskiy aide.

Sondland’s name also appears in the intelligence community whistleblower complaint, which says that the day after Trump’s July call with Zelenskiy, Sondland and Volker met with Zelenskiy in the Ukrainian capital. The whistleblower describes Sondland as working to help the Ukrainians navigate Trump’s request for an investigation and trying to mitigate damage Giuliani was allegedly inflicting on U.S. national security.

But in the text messages that Volker ultimately turned over to Congress, Sondland appears to not only be actively facilitating Trump’s goal but also shutting down a top diplomat who raised concerns.

On Sept. 9, according to the messages, acting Ambassador to Ukraine Bill Taylor tells Sondland that “as I said on the phone, I think it's crazy to withhold security assistance for help with a political campaign.” Sondland pushes back, telling Taylor that he’s “incorrect” about Trump’s intentions and that the president has made clear “no quid pro quos of any kind.” He then advises Taylor to stop discussing the issue via text.