WASHINGTON — Gordon Sondland, the US ambassador to the European Union, will testify before the committees leading an impeachment inquiry into US President Donald Trump, his lawyers said on Friday, after the Trump administration had earlier blocked his appearance.

Sondland, a Trump political donor, was initially scheduled to testify before the House of Representatives committees on Tuesday and had flown from Brussels to do so, but the State Department had said he was not allowed to appear before what Trump has decried as a "kangaroo court."

"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," his lawyers, Robert Luskin and Kwame Manley, said in a statement.

But Sondland is not authorized to release the documents the House committees have sought, his lawyers said, adding that Sondland hopes the material will be shared with the committees before his Thursday appearance.

A person familiar with the negotiations between the committee and Sondland's legal team said there has been no contact between the ambassador and the White House since Sondland was directed not to testify.

The White House did not immediately respond to a request for comment.

House Democrats launched an impeachment inquiry to investigate Trump after a US intelligence official filed a whistle-blower's complaint about a July 25 call between the US president and Ukrainian President Volodymyr Zelenskiy.

In the call, Trump pressed Zelenskiy to investigate his political rival Joe Biden, a former US vice president and a leading candidate seeking the 2020 Democratic presidential nomination.

The whistle-blower's complaint also raised concerns about the classification of the call and other calls between Trump and foreign leaders.

Sondland participated in text messages about Washington's relationship with Ukraine with other top diplomats. House Democrats received a cache of the texts as part of their impeachment inquiry.

The White House has said it would not cooperate with the impeachment inquiry, which it says is illegitimate and constitutional. — Reuters