US energy secretary Rick Perry will leave his job by the end of the year, President Donald Trump has said.

Mr Perry was travelling with Mr Trump to Texas when he told Mr Trump of his decision aboard Air Force One.

Mr Perry is under scrutiny over the role he played in the president’s dealings with Ukraine, which are currently the subject of an impeachment inquiry.

House Democrats have subpoenaed Mr Perry for documents related to a Ukrainian state-owned energy company as well as his involvement in a July call between Mr Trump and Ukrainian President Volodymyr Zelenskiy. The members of Congress set a Friday deadline.

Mr Trump has said Mr Perry teed up the July 25 call, in which Mr Trump pressed Ukraine to investigate his Democratic rival Joe Biden and his son, who was employed by a Ukrainian gas company.

Mr Perry did not answer questions about his decision upon arrival in Fort Worth.

Mr Perry alighting from Air Force One Credit: AP/Andrew Harnik

A spokeswoman for Mr Perry, Shaylyn Hynes, has said he wanted Mr Trump to speak with the Ukrainian leader on energy matters related to US efforts to boost Western energy ties to Eastern Europe. It is part of a long-term effort to lessen the political control Russia wields through its dominance of the fuel supply.

The Associated Press reported this month that a circle of businessmen and Republican donors touted their connections to Mr Trump and his personal lawyer, Rudy Giuliani, as they sought to install new management at the top of Ukraine’s state-owned gas company last spring.

The plan hit a snag after Mr Zelinskiy’s election, but Mr Perry took up the effort to install a friendlier management team at the company, Naftogaz. Mr Perry, a former Texas governor and Republican presidential candidate, attended Mr Zelinskiy’s May 2019 inauguration as the administration’s senior representative and met privately with Mr Zelinskiy. He has denied any wrongdoing.