(CNN) The former national security adviser to President Donald Trump said it is "absolutely not" appropriate for a president to ask other countries to interfere in the political process of the US.

Retired Army Lt. Gen. H.R. McMaster spoke on a panel during an event at The Foundation for Defense of Democracies on Thursday, when a reporter asked him if it is appropriate for a president to solicit foreign interference in the US political process.

"No, it's absolutely not," McMaster replied.

The comment comes as McMaster's former boss faces an impeachment inquiry, centered on a July phone call in which he pressed Ukrainian President Volodymyr Zelensky to investigate former Vice President Joe Biden and his son, Hunter, according to a rough transcript of the call released by the White House. There is no evidence of wrongdoing by Joe or Hunter Biden in Ukraine. During that call, Trump also asked Zelensky to investigate the 2016 election, leaving at least one White House official "shaken" by what took place.

Trump himself has maintained that he did nothing wrong in the call and later, when speaking to reporters outside the White House, said he also hoped China would investigate the Bidens. The statements from the phone call with Zelensky and to reporters on the White House lawn have deeply troubled national security officials.

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