WASHINGTON (BLOOMBERG) - President Donald Trump has promoted a White House aide who was subpoenaed in the House impeachment investigation but declined to testify.

The aide, Mr Robert Blair, has been named a special representative for international telecommunications policy, the White House said in a statement on Monday evening (Dec 23).

Mr Blair, according to the statement, will "coordinate interagency efforts and serve as a liaison to industry, non-governmental, and international stakeholders to promote the development, deployment, and operation of the next-generation telecommunications infrastructure" and support the administration's policies regarding 5G technology. He will report to Mr Larry Kudlow, the White House economic adviser.

He will continue in his capacity as an assistant to the president and senior adviser to Acting Chief of Staff Mick Mulvaney, the White House added.

Mr Blair was among the administration officials who were subpoenaed by the House impeachment committees in the fall, but did not appear under direction from the White House, which cited advice from the US Justice Department.

Investigators wanted to talk to him about the Trump administration's decision to put off security aid for Ukraine.

According to the House report on the Ukraine inquiry, Mr Blair sent an e-mail "on or about July 12" to Mr Michael Duffey, an official at the Office of Management and Budget, explaining that the "president is directing a hold on military support for Ukraine".

The report also said that Mr Blair was among the officials who listened in on the July 25 telephone call between Mr Trump and Ukrainian President Volodymr Zelensky.

Senate Minority Leader Chuck Schumer has asked that Mr Blair and Mr Mulvaney along with Mr Duffey and former National Security Adviser John Bolton, testify at the impeachment trial in the Senate.

So far, Mr Schumer's request for the witnesses has been rebuffed by Senate Majority Leader Mitch McConnell.