White House counselor Kellyanne Conway on Monday hit back at Sen. Bob Corker in a continuing war of words between the Trump administration and the retiring Tennessee Republican, criticizing the senator's Sunday tweet likening the White House to an "adult day care center" as "incredibly irresponsible."

"We've all worked with Sen. Corker over the years, we thank him for his service, but I find tweets like this to be incredibly irresponsible," Conway said on " Fox & Friends ." "It adds to the insulting that the mainstream media and the president's detractors … it adds to their ability and their cover to speak about a president of the United States – the president of the United States – in ways that no president should be talked about."

Conway also implied that Corker should have aired his grievances privately.

"I still come from a background where you express yourself privately, and this president has the most open-door policy to our senators and our members of Congress that I think anybody's ever seen," she said.

Conway's comments followed a day of diatribes between Corker and President Donald Trump, which began with Trump himself tweeting Sunday that Corker had " begged " him for a re-election endorsement. The president also blasted the senator for his role in " the horrendous Iran deal ."

"Hence, I would fully expect Corker to be a negative voice and stand in the way of our great agenda. Didn't have the guts to run!" Trump wrote .

Corker, who announced last month he would not seek re-election to the Senate in 2018, responded with the "adult day care" tweet:

It's a shame the White House has become an adult day care center. Someone obviously missed their shift this morning. — Senator Bob Corker (@SenBobCorker) October 8, 2017

The two-term senator and chairman of the chamber's Foreign Relations Committee then continued his criticism in an interview with The New York Times, saying Trump was treating the presidency like "a reality show" and that he posed a danger of putting the U.S. "on the path to World War III" by threatening other countries.

"He concerns me," Corker said. "He would have to concern anyone who cares about our nation."

Corker also disputed that he had begged for Trump's endorsement in order to run again next year, and said Trump had pushed him to launch another bid for office.

"I don't know why the president tweets out things that are not true," he said. "You know he does it, everyone knows he does it, but he does."

Corker, once considered a contender to be Trump's vice presidential running mate and a candidate for secretary of state, has sparred on another recent occasion with the president, criticizing Trump's response to racially charged violence in Charlottesville, Virginia.

On Sunday, he repeatedly told the Times that he liked Trump and wished him "no harm."

According to the Times, Trump's initial Twitter shots on Sunday may have been prompted by a cable news repetition of Corker saying Secretary of State Rex Tillerson was an official helping to "separate our country from chaos" – a comment that itself followed a report that Tillerson had previously called Trump a "moron."