Tate Modern 's Expansion

Britain's leading art galleries and museums, including Tate Modern and the Victoria & Albert, will have to scale down their exhibition and expansion plans as recession threatens millions of pounds in business sponsorship.

The V&A is hoping to attract £120m for "phase two" of its exhibition plans, Tate Modern is seeking £125m for an extension and the National Gallery and National Galleries of Scotland need £100m to save two Titian paintings for the nation by 2012. But they might not be able to realise their ambitions if the economy stays in the doldrums. Colin Tweedy, chief executive of the organisation Arts & Business, said that scaling down shows would be an "inevitability". He said: "I'm trying to be optimistic but these are incredibly worrying times for people trying to raise money. If this recession is short and sharp and projects can be delayed or extended, all will get their money. But if it drags on, I can't see they will all do it."

His warning came as figures revealed business sponsorship was down by 7 per cent in 2007-8. While Mr Tweedy said the drop was likely to be cyclical, an attitudinal survey conducted by Arts & Business asking companies if they would be giving more or less over the next few years found great nervousness among sponsors.

Mr Tweedy predicted business sponsorship would slow until 2013: "Because of the time lag with art and sponsorship, if you talk to art galleries, their sponsorship continues. But the arts can't be immune from the downturn, although I think it could suffer less than sports sponsorship which has traditionally been higher," Mr Tweedy said. "Sponsors are delaying rather than pulling sponsorship right now, or taking longer to confirm sponsorship." The Earl of Cadogan, the 17th-richest man in Britain, reportedly decided not to plough £37,000 into the Chelsea Art Festival, which he had backed for 15 years. The event has been cancelled.

Alistair Spalding, the chief executive of Sadler's Wells, revealed that while current sponsors were "honouring their commitments", the theatre was finding it tough. "Fresh opportunities are very hard to come by. It's the last thing these companies are going to be thinking about," he said.

An exhibition of works by the Italian architect Andrea Palladio at the Royal Academy of Arts had trouble finding funding. In the end, the architects Lord Foster and Lord Rogers and a group of Royal Academicians stepped in.

The National Gallery attracted individual American philanthropists rather than corporate sponsors for a show on religious Spanish sculpture. Emma Collings, head of corporate fundraising at the National Gallery, said: "We are concerned, but the National Gallery is fortunate to have in place a three-year partnership with Credit Suisse and a strong upcoming exhibition schedule."

Arts funding: Projects under threat

*Titian £100m

Thirty-seven of Britain's leading artists campaigned with the National Gallery and National Galleries of Scotland in an attempt to keep two Titian paintings, Diana and Acteon, and Diana and Callisto, from being sold to foreign buyers. It is expected to be announced today that £50m has been raised to buy Diana and Acteon.

*Tate Modern extension £125m

Nicholas Serota, the director of Tate Galleries, said he hoped the money would be raised by 2012. The gallery has a third of the funding. The revised plans await planning permission.

*V&A's extension plans £120m

The museum has secured the £120m funds for the first phase, but the second phase will cost another £120m, to create more gallery spaces for fashion and textiles, photography and furniture. The museum is making feasibility studies of the development project.