The University of Sussex has been accused of trying to keep staff “in the dark” over plans to privatise more than one in ten jobs.

Unions at the university say bosses have not told them which companies it is speaking to about running its catering, estates and facilities and conference services.

The changes will mean 235 staff will be transferred to private firms.

The unions described the current bidding process as “poorly considered and secretive” and called on the university to start consulting properly with staff.

In May members of the University and College Union (UCU), Unison and Unite, supported by students, held a series of protests against the proposed outsourcing.

They are worried it will lead to a two-tier workforce as staff are employed on different terms and conditions.

Rob French, the branch chairman at Sussex UCU, said: “Sussex must come clean over who it is talking to about running these services.

“The university seems intent on steamrollering these plans through without any proper consultation or thought about the risks outsourcing poses.

“This is not the way to reward loyal staff who have years of expertise in helping to support the needs of students.”

The university, which employs 2,200 people, has previously said it wants to cater for a growing number of students.

The number of students has risen from 10,000 to 12,000 in the past two years and is expected to reach 15,000 by 2015.

Annually, the university takes in £170 million, of which about £45 million comes from the Government.

It says the move is not about trying to reduce staff numbers as workers would be transferred to the providers taking over the services.

A university spokeswoman said: “We are following a carefully managed procurement process in accordance with EU procurement regulations. We are following precisely the process and timescale as laid out in May when we first informed staff and unions of our plans.

“We are currently in dialogue with potential bidders – as we said we would be doing at this stage – and this remains commercially confidential until a preferred supplier is identified.”

The transfer is planned for August 2013.