A trade union has expressed “great concern” over proposals for the future of Barnet’s library service.

A range of options have been laid out to help save £8million, which include closing libraries, reducing their size, leaving them unstaffed and making greater use of volunteers.

Library staff were briefed earlier this week about the proposals, which will be discussed at a meeting of the children’s, education, libraries and safeguarding committee next Tuesday.

In an address to members, seen by the Times Series, the union said: “Our pay, terms and conditions are likely to worsen as has happened to other ex-Barnet workers, that is for those who hold on to our positions as there will be job losses with staff only being on site from up to 50 per cent of current opening hours.”

Proposals for the library service also suggest extending opening hours by leaving libraries unstaffed, which Unison said would put the safety of the public at risk.

Unison said: “Staff opening and closing the library at the beginning and end of unstaffed hours will also be put at extra risk.

“Until we have evidence from the council, Unison believe unstaffed libraries pose a great danger to our members, our other colleagues and to the general public.”

The union also questioned whether the reorganisation of libraries would save money, or whether unstaffed hours would make thefts more likely.

Making greater use of volunteers to help run the service was also questioned, a move Unison claimed would put the libraries at risk of “eventual closure”.

The letter added: “Nationally it is far from being proved that volunteer-managed libraries have the staying power to operate in the long term once initial enthusiasm and funding dwindles or ceases.”

The proposals are being put forward to help contribute to the £72million the council needs to save over the next six years.

Officers have recommended the committee agree three proposals for the future of the service, which will then be put out to public consultation.

Following the consultation, a further report will be presented to the committee in January 2015.