Former Secretary of State Rex Tillerson on Monday told the PBS NewsHour that asking for personal favors and using United States assets as collateral is “wrong.”

Tillerson spoke with NewsHour anchor and managing editor Judy Woodruff at a luncheon hosted by the University of Texas MD Anderson Cancer Center in San Antonio. Tillerson discussed reports that President Donald Trump pushed to withhold from Ukraine nearly $400 million in military aid until the country’s president agreed to open investigations into political rivals, including former Vice President Joe Biden.

“If you’re seeking some kind of personal gain and you’re using — whether it’s American foreign aid or American weapons or American influence — that’s wrong. And I think everyone understands that,” he said.

Clearly, asking for personal favors and using United States assets as collateral is wrong.

His comments came as House lawmakers enter the second week of public hearings in the impeachment inquiry into Trump’s actions in Ukraine. Last week, Bill Taylor, the top U.S. diplomat for Ukraine, and George Kent, the deputy assistant secretary of state for European and Eurasian affairs, testified that they believe Trump’s personal lawyer Rudy Giuliani sought to “dig up political dirt” on rivals in order to benefit Trump in the 2020 election. Tillerson said he believes the actions that have raised concerns among congressional Democrats began after the president removed Tillerson from his role as secretary of state in March 2018.

Tillerson also addressed allegations from the former U.S. Ambassador to the United Nations Nikki Haley that he and former White House chief of staff John Kelly tried to recruit her to subvert the president.

“[There are] so many people still [in the administration] trying to serve the country, so when people write books that quickly after leaving, my guess is [there are] two motivations: They need the money and they need the political future,” Tillerson said.

Tillerson also rejected Haley’s interpretation of a meeting during which she says Tillerson and Kelly allegedly hatched a “plan to save the country.”

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“I recall the meeting,” Tillerson said. “But at no time in that conversation do I have any recollection at all of any discussion suggesting that she needed to join some effort of ours.” He denied that he and Kelly were ever trying to undermine the president.

Worries about leaks and internal resistance have plagued the Trump administration. Another book written by an official who has remained anonymous is set to be released next week.

During his conversation with Woodruff, Tillerson did not criticize the president directly. But when asked whether the country is in good hands with Trump, he responded, “I think the country is in good hands with the American people.”

“I don’t worry about the future,” he said. “I believe the American people are smart. I believe the American people ultimately, if they see something that they don’t feel is serving the American people or serving our national security,” they will make a change.