Eight trade unions, including Prospect, today issued more details about the launch of their joint Lost Arts campaign and website - at a rally and lobby of parliament on Wednesday 15 June. Prospect members are urged to write to their MPs, attend the launch rally and arrange appointments with their MP on the day.

Lost Arts will record all the projects, initiatives and organisations that will be lost due to the cuts in public funding for the arts. The website will also keep a running total of the money lost to the arts, the money lost to the Treasury, and the number of jobs at risk.

The launch event will take place at 1pm in the Lecture Hall, Westminster Central Hall. Speakers include actress Maggie Steed, Alison McGovern MP, and John Smith, President of the Federation of Entertainment Unions.

Prospect will be taking part on behalf of more than 5,000 specialists at leading heritage institutions, including English Heritage, Science Museum, British Museum, British Library, Imperial War Museum and National Galleries of Scotland.

Prospect General Secretary Paul Noon said: "Thousands of people with unique skills are set to lose their jobs in museums, galleries, national libraries and heritage organisations. This joint campaign aims to highlight the terrible damage these cuts will cause, and persuade the government to change direction.

"The public will lose access to the nation's treasures or end up having to pay for access to them. The economic cost to the country will be immeasurable. That is why Prospect is proud to be involved."

FEU President John Smith said: "I'm delighted that we have been able to secure support for this important initiative from such a wide cross section of unions. For every £1 that the Arts Council invests, an additional £2 is generated from private and commercial sources, totalling £3 income.

"At a local level our investment can lever five times its worth and yet the arts and culture sector is currently suffering from disastrous local authority cuts, as well as the cuts that the Arts Council has had to make after its 30% cut from government.

"These cuts signal the start of the end for many organisations, and we want to make sure that these losses are documented. By keeping an account of the damage done on the Lost Arts website , we hope to win the argument for public funding of the arts once and for all."

The unions involved in Lost Arts are: Musicians' Union, Equity, the Writers' Guild of Great Britain, National Union of Journalists, BECTU, Unite, Prospect and PCS.

In March, the Arts Council announced the removal of funding from more than 200 organisations from 2012.

Details are still emerging of how cuts to museums and galleries will impact in Prospect areas, but already announced are:

• up to 32 per cent cuts at English Heritage, with over 200 redundancies
• 200 redundancies at the British Library as it moves to digitisation
• 15 redundancies at the Museum of London and privatisation of the archaeological service
• redundancies at the Imperial War Museum
• a 10 per cent staffing cut at the National Museum of Science and Industry
• 4 per cent cuts at the National Galleries of Scotland.