CNN has filed a lawsuit against US President Donald Trump and top aides after the White House banned one of the broadcaster's most prominent reporters.

The suit demands that reporter Jim Acosta's access to the White House be reinstated. The White House took away Acosta's Secret Service-issued "hard pass" last week after a heated exchange between him and Trump at a press conference.

The White House dismissed the lawsuit as "more grandstanding" from CNN and vowed to "vigorously defend" itself against the case.

Spokeswoman Sarah Sanders said CNN had more than 50 reporters with hard passes and insisted that Acosta's behaviour last week was "neither appropriate nor professional."

The White House has alleged that Acosta made physical contact with a member of staff who was seeking to retrieve the microphone after the reporter asked a question and then continued to ask further queries of the president.

"This was not the first time this reporter has inappropriately refused to yield to other reporters," Sanders said.

The lawsuit CNN filed is based on First Amendment grounds, the constitutional guarantee of free speech and freedom of the press.

"While this suit is specific to CNN and Acosta, this could have happened to anyone," CNN said in a statement.

The president has a history of tensions with CNN and Acosta.

The network received the backing of the White House Correspondents' Association, which said that Acosta's credential "should not have [been] taken away in the first place."

"The President of the United States should not be in the business of arbitrarily picking the men and women who cover him," the journalists' association said.