Washington DC - The US Congress has been quietly pushing back against President Donald Trump's attempts to take over the esteemed Library of Congress.

Last week, Trump faced heavy backlash after he abruptly fired head librarian Carla Hayden – the first woman and African American to ever hold the position.

According to The Washington Post, Trump is now attempting to install current Deputy Attorney General Todd Blanche, who has also served as his personal defense attorney, though no official announcement has been made.

But in an email obtained by the Post, top career official Robert Newlen sent a letter to staff on Monday, announcing he will take over Hayden's role until further notice.

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"You may have read that the White House has named a new acting Librarian," Newlen wrote.

"Currently, Congress is engaged with the White House, and we have not yet received direction from Congress on how to move forward. We will share additional information as we receive it."

The library is specifically run by Congress and the legislative branch, while the president only has the ability to nominate an individual to lead it. Critics have argued that Trump's move threatens the separation of powers and is a part of a broader goal to gain control of the institution.

On Tuesday, House Minority Leader Hakeem Jeffries described the efforts as "an example of executive overreach," and Senator and Rules and Administration Committee member Alex Padilla said he has been speaking with Republican colleagues "on defending the legislative branch."

Republicans have also voiced some opposition to Trump's efforts. Senate Majority Leader John Thune told reporters on Tuesday that Trump must go through Congress before enacting such unprecedented changes.

"We made it clear that there needs to be a consultation around this – that there are equities that both Article I and Article II branches have [with] the Library of Congress," Thune said, referring to the legislative and executive branches.

Thune went on to say that Trump administration officials have been meeting with the Rules Committee, which oversees the library, to discuss a resolution to the matter.