The Union of Jewish Students has said it is “unacceptable” that two students linked to extreme Islamist organisation Hizb ut-Tahrir have been elected to lead a university student union.

Tarik Mahri and Jamal Achchi were elected by University of Westminster Students’ Union members despite the NUS’s no-platform policy for the radical group.

The pair promoted themselves, along with a third candidate, as the “three brothers” and appealed to fellow students to back them to tackle student debt and finance issues.

Mr Mahri, who will take on the role of union president this summer, describes himself as an “outspoken” political activist and has used Twitter to post messages supportive of Hizb ut-Tahrir.

Mr Achchi shared posts promoting Hizb ut-Tahrir ideologies on the social publishing site scribd.com. They include one document explaining methods that could be used to establish an Islamic Caliphate.

Carly McKenzie, UJS campaigns director, said: “This is a truly unacceptable and deeply concerning move by UWSU. Hizb ut-Tahrir ideology directly contravenes the values held by students and their union.

“How these candidates can seek to properly represent all students is beyond me. What's the use of the NUS no platform policy?”

Last month UJS formally complained to the union about the candidates. The election was later postponed, with the union executive saying the delay was due to problems with the election rules which gave some candidates an unfair advantage.

The same candidates were allowed to stand when the election reopened. Mr Mahri and Mr Achchi were successful, while the third of the “three brothers”, Adeel Anwar, narrowly missed out on the role of vice-president for communications.

In February last year an event with a Hizb ut-Tahrir representative, due to take place on the university’s campus, was cancelled following pressure from NUS.

Mr Mahri is a British rapper and political activist of Algerian descent. He also supports the creation of an Islamic Caliphate. His Twitter postings reflect anti-American, anti-Israel leanings, and include the messages supportive of Hizb ut-Tahrir ideals.

Jamal Achchi was elected vice-president for education. He is a fourth year Arabic and international studies student, who describes himself as a “political activist” and youth worker.

NUS president Aaron Porter is believed to have contacted outgoing UWSU president Robin Law to voice his concerns at the election result.

Mr Porter said: "Our rules state individuals or members of organisations or groups identified as holding racist or fascist views are not allowed to stand for election or go to, speak at or take part in conferences, meetings or any other events."

The NUS will formally consider issues around the university vote at a committee meeting next month.