US President Donald Trump is waging a war of words with legendary Watergate reporter Carl Bernstein over a story about his ex-lawyer Michael Cohen.
On Wednesday, the president called Mr Bernstein a "sloppy" and "degenerate fool" who invented stories, reports BBC.
Mr Bernstein fired back on Thursday, tweeting that he spent his life "bringing the truth to light" and "no taunt" could diminish that commitment.
His story reported Mr Trump knew about a 2016 meeting with Russians.
On Twitter, the president said "CNN is being torn apart from within" over refusing to admit their mistakes, adding that Mr Bernstein "is being laughed at all over the country".
Mr Bernstein, a famed journalist who covered the Watergate scandal during the Nixon presidency, responded saying he stands by his reporting.
The story in question had quoted sources as saying that Mr Cohen, the president's former personal lawyer, was ready to testify that Mr Trump was aware of the June 2016 Trump Tower meeting between his son, Donald Trump Jr and Russians who said they had dirt on Hillary Clinton.