US presidential debate sees Green Party outsider candidate Jill Stein KICKED OUT of university campus hosting showdown between Donald Trump and Hillary Clinton

THE fourth-place outsider in the US presidential election has been BANNED from the blockbuster debate between Hillary Clinton and Donald Trump.

Green Party nominee Dr. Jill Stein was escorted by police off the university campus hosting the front-runner clash just hours before it was due to begin.

She was holding a demonstration for eco-warrior activists on the grounds of Hoftsra University in Long Island, New York when police removed her.

It is the same spot that she was arrested in 2012 for protesting during the debate between Barack Obama and Republican opponent Mitt Romney during that year's presidential contest.

Stein couldn't provide documents to police permitting her to be in the area according to Nassau County PD.

It came amid tight security before the bout between the Democratic and Republican heavyweights.

“We were immediately escorted off of the Hofstra campus after the press conference just now and told not to do any more press,” she .

“She was on the college campus, we asked to verify for proper credentials, she did not have them, and she was nicely escorted off the campus," a police spokesperson told .

The far left long-shot, who has called for campaigners to "occupy" the debates, is languishing with a 2.4% rate of support in polls -- well below the 15% required to join the televised showdown.