There are still 28 days left until President-elect Donald Trump will take the oath of office, but NPR host Diane Rehm is already expressing concern about how he will use his executive powers once in the White House.

In a segment on her daily talk show Thursday, Rehm was speaking with Juliet Eilperin, the Washington Post‘s White House bureau chief, when the host said she is worried that Trump and his administration are already expanding executive authority even though he has not yet taken office.

Rehm referenced the Trump transition team's questionnaire that was sent out to current Energy Department employees requesting details on those who had worked on President Obama's climate change initiatives. The questionnaire she was referring to also asked the employees to state whether they had attended United Nations climate change conferences.

"Isn't that sort of expanding executive authority beyond the authority of the people at the top of that agency?" Rehm asked Eilperin, who responded by giving more details on the questionnaire and the department's response.

Trump has yet to issue any executive orders or take other executive actions because he has not been inaugurated. He has promised to undo many of the executive orders issued by President Obama, however.

Obama has been criticized by Republicans for his expansive use of executive orders regarding hot-button issues such as labor, climate change, and immigration. The president has defended his use of executive orders by blaming congressional Republicans for inaction on his legislative priorities.

Just this week, Obama advised Trump in an interview with NPR to not rely on executive orders to implement legislation. Obama said that he "bent over backwards" to try and find compromise with congressional Republicans on important legislative issues and only resorted to executive orders when he was not able to do so.

Rehm has hosted her daily current affairs talk show on NPR since 1979 and was awarded the National Humanities Medal in 2014 by Obama. Last December she announced that she planned to retire after the 2016 election.