WASHINGTON – Appearing in television interviews on Sunday morning, Defense Secretary Mark Esper said he would comply with a subpoena issued by House Democrats as part of an impeachment inquiry into President Donald Trump's pressuring of the Ukrainian government to open investigations into former Vice President Joe Biden and his son Hunter Biden.

House Democrats had issued subpoenas to Esper and the Defense Department for documents related to Trump's withholding of military aid to Ukraine, which they believe may have been part of the pressure on Ukraine to open investigations.

“We will do everything we can to comply," Esper said to host Margaret Brennan on CBS' "Face the Nation."

"Yeah we will do everything we can to cooperate with the Congress. Just in the last week or two, my general counsel sent out a note as we typically do in these situations to ensure documents are retained," Esper said.

Esper reiterated the point in several other appearances on Sunday morning talk shows, though on "Fox News Sunday," he did not make a commitment to meeting the subpoena's deadline of Tuesday, Oct. 15.

"I don't know the status of what that document preparation is, what restrictions we may have internally with regard to releasing them, the White House has a say on the release of documents as well," he said.

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The White House has vowed not to cooperate with the impeachment inquiry, calling it a "coup" and a "partisan" inquiry. Other White House officials like Secretary of State Mike Pompeo have missed subpoena deadlines but said they would comply with the law.