Outgoing Energy Secretary Rick Perry said Friday that his plans to resign are not related to the ongoing congressional impeachment inquiry into his role in the Ukraine affair, but because he wants to spend more time with family in Texas.

The comments from Perry, who said he plans to step down by the end of the year, came on the same day he and Energy Department lawyers told Congress they would not comply with a Friday deadline to respond to a congressional subpoena to provide information related to his work in the former Soviet republic.

Last week, the chairmen of the House Intelligence, Oversight and Foreign Affairs committees subpoenaed Perry to provide documents related to his role in U.S. energy policy in Ukraine and whether he was involved in decisions to withhold military aid.

But Perry responded Friday in a letter to the committees that, in accordance with a previous White House letter rejecting other subpoenas, he would not comply until the House votes to authorize the impeachment inquiry. Department lawyers also argue some of the documents requested are covered by executive privilege.

“Pursuant to these concerns, the Department restates the President’s position: “Given that you inquiry lacks any legitimate constitutional foundation, any pretense of fairness, or even the most elementary due process protections, the Executive Branch cannot be expected to participate in it,” the Energy letter says, citing the White House letter.

With regard to his leaving Washington, Perry said, “I've been looking at this for some time,” in an interview on CNBC Friday.

“I don't think anybody's surprised that, you know, I've got a rather intense love affair with this state, my wife, this little town of Round Top where we have chosen to live. And so the lure became overwhelming for me to come back home and to spend time with the people that I really love," he said.

President Donald Trump announced Friday on Twitter that he plans to nominate Deputy Energy Secretary Dan Brouillette to replace Perry. Brouillette is an Army veteran from San Antonio, Texas, and has previously worked in the energy sector including as assistant secretary for congressional affairs at the Energy Department from 2001 to 2003. More recently he worked as an executive for Ford Motor Company and USAA.

As part of the impeachment inquiry, Perry has been subpoenaed to provide documents related to his work in Ukraine and meetings with other officials involved in the region.

Perry has said previously that he planned to cooperate with the congressional requests. But since then, the White House has defied those requests because it regards the impeachment inquiry as illegitimate without an official House vote.

Perry has been referred to by some of his colleagues as one of the "three amigos" of the administration's policy in Ukraine. Members of Congress are investigating whether the White House withheld military aid to the country or offered a White House summit on the condition Ukrainian officials investigate former Vice President Joe Biden and his son, Hunter.

Perry has not been accused of wrongdoing and insists his efforts in Ukraine were focused on advancing American interests in the region by promoting reforms to address corruption and bringing in American energy companies to get Ukraine away from Russian natural gas.

Perry said he's happy with the goals he's accomplished in his time at the Energy Department, including pushing for more American natural gas in Europe and for Ukraine to tackle corruption in the country.

"The timing was right for me. I got these big things done, the agency is in great shape, it's going to continue to be focused on the areas that are important to America. So it was a right time for me to come back home," he said in the interview.

In recent months, Perry and the Energy Department have frequently denied reports he planned to resign. Perry said Thursday morning he was one day closer to stepping down "but it ain't today." He gave Trump his resignation notice later that day.

Perry has defended the administration’s handling of Ukraine, saying the Biden name was not brought up in his conversations with the president and other officials. Perry told Fox News he never heard the Biden name in conversations with Ukrainian officials or the White House, but that the U.S. was pushing Ukraine to crack down on corruption in the country.

He also defended White House acting Chief of Staff Mick Mulvaney, who said Thursday the administration did ask Ukraine for an investigation of Democrats in the 2016 election before aid money would be released. Mulvaney later said in a statement that his comments did not mean there was a "quid pro quo" but Perry said Friday that Mulvaney was being "straight up" and that the administration was "hammering" Ukraine to tackle corruption.

"People are trying to connect dots. By basically saying that there was no quid pro quo in the sense of what those folks out there would like for it to be. That we'll give you this money unless you go investigate Joe Biden and his son. I never heard that anywhere, any time, in any conversation," he said on Fox News.