Architect Alejandro Zaera-Polo has filed a lawsuit against Princeton University for libel and breach of contract, after he was asked to step down as head of its architecture school over allegations of plagiarism.

The architect, who was head of Princeton University School of Architecture until his forced departure, is claiming damages and legal costs against his former employer on four counts.

Zaera-Polo's lawyers initiated a civil action against the university yesterday, submitting a civil action complaint to the Superior Court of New Jersey.

"This is an action for breach of contract, breach of the implied covenant of good faith and fair dealing, tortious interference with prospective economic advantage, trade libel, and defamation," states the complaint, which was leaked anonymously to Dezeen.

Zaera-Polo confirmed he had initiated legal action but did not comment further. "I filed a lawsuit in the New Jersey courts," he told Dezeen.

The lawsuit relates to a series of events in 2014 that culminated in Zaera-Polo's departure from the School of Architecture at Princeton in October that year.

The university, regarded as one of the most prestigious in the world, asked the Spanish architect to resign amid claims he had used plagiarised written material in texts prepared for the 2014 Venice Architecture Biennale, where he curated a section of the Elements of Architecture exhibition.

Texts produced by Zaera-Polo for the Facade section of the exhibition allegedly contained passages similar to those previously published by sources including Wikipedia.

The resulting row saw architect Rem Koolhaas, who curated the Biennale, accuse Princeton of making a "category error" by expecting one of its faculty staff to adhere to rigorous academic standards when preparing written material for a public exhibition.

"The point from the beginning was to make a publication accessible to any reader," Koolhaas wrote in an email to Princeton president Christopher Eisgruber.

The 14-page legal document submitted by Zaera-Polo's lawyers this week claims that the architect's departure from the architecture school was "interpreted as an admission of wrongdoing".

It accuses Princeton of "aggressive treatment" of the Spaniard and says the university unfairly refused to authorise a full and independent expert investigation into the circumstances leading up to Zaera-Polo's departure.

"The defendant's actions and failures have resulted in significant damages to the plaintiff's business and his reputation, including the loss of lucrative and prestigious professional and academic opportunities," the document states.

Princeton University did not respond to requests for a comment.

Zaera-Polo was born in Madrid in 1963. He worked at OMA in Rotterdam under Koolhaas before establishing Foreign Office Architects in London with Farshid Moussavi in 1993.

Following the break-up of FOA he formed Alejandro Zaera-Polo Architecture in 2011, which became Alejandro Zaera-Polo and Maider Llaguno Architecture (AZPML) when he went into partnership with Maider Llaguno in 2013.

Update 26/05/16: Princeton University has sent us the following statement:

"The University is aware that Professor Zaera-Polo has filed an action against it and others relating to the investigation and disposition of research misconduct claims asserted against him and to his resignation as Dean of the School of Architecture. As noted in the Rules and Procedures of the Faculty, the 'University is committed to high scholarly standards in the substance of research and to high ethical standards in the conduct of research' and to the fair and unbiased adjudication of all misconduct complaints.

"The University is confident that the officials and faculty members who investigated and adjudicated the claims against Professor Zaera-Polo did so fairly and in accordance with University policies and procedures. The University will defend its position in court, and looks forward to the successful resolution of these claims."