Trump first announced last Friday he was barring the three outlets from the White House, accusing them of writing "fiction or lies" about his administration.

By Saturday morning, each outlet reported that they were denied entry to the White House grounds and that their press badges were confiscated.

All three outlets accused the Trump administration of violating their constitutional rights.

In a joint statement on Monday, they said they were pursuing legal action to "defend the principle that the government does not decide what the press reports".

More than 50 media organisations across the ideological spectrum filed an amicus brief in support of the lawsuit, including Fox News, the New York Times, the Washington Post and the Wall Street Journal.

There have been previous instances of administrations attempting to limit certain outlets' access.

The Obama administration tried to exclude Fox News from participating in a specific press pool interview with an administration official in 2009.

But after objections from the other four networks in the press pool, Fox News was allowed in.

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