Rick Perry tells President Trump he's out as energy secretary amid increasing attention from Ukraine controversy

Energy Secretary Rick Perry sent a letter announcing his intended resignation to President Donald Trump on Thursday, amid reports of disagreement between the two over the ongoing Ukraine controversy and related impeachment efforts.

"It has been a tremendous honor to serve our country in your administration in such a meaningful way," Perry wrote in his letter. He added that he "will be forever grateful for this opportunity and I look forward to further supporting you and advancing American leadership in significant ways as a private citizen.

"Please accept this letter as my official notification that I plan to resign at a date later this year," Perry concluded.

In a video message to Department of Energy employees, Perry called the position "the coolest job in the world."

The resignation announcement comes as Perry has become a major figure in the narrative about President Trump's outreach to the Ukrainian officials, which is the basis of the Democrats' latest impeachment efforts. During a conference call with Capitol Hill Republicans earlier this month, Trump reportedly blamed Perry for the July 25 phone call with Ukrainian President Volodymyr Zelensky.

"Not a lot of people know this but, I didn't even want to make the call," Trump said, according to an Axios report. "The only reason I made the call was because Rick asked me to. Something about an LNG [liquid natural gas] plant."

A DOE spokesperson later said that "Secretary Perry absolutely supported and encouraged the president to speak to the new president of Ukraine to discuss matters related to their energy security and economic development" and that he "continues to believe that there is significant need for improved regional energy security."

Perry's role in the matter goes deeper than just the phone call, according to other Trump administration officials.

The secretary led an official May delegation to the Ukraine that Ambassadors Kurt Volker and Gordon Sondland have both testified about to House investigators. It was after that trip, both men testified, that members of the delegation met with a President Trump to convince him of recently elected President Volodymyr Zelensky commitment to reform, and the importance of U.S. assistance to the country.

In both accounts, Trump was "skeptical" of the prospect, given the eastern European country's notorious history of corruption.