LONDON (Reuters) - A question mark hangs over the future of Spanish rock festival Benicassim after its owners said on Friday that they had been unable to secure the funding they had been seeking in recent weeks and asked that its London-listed shares be suspended.

Music Festivals Plc had warned in August that it would make a loss in 2012 after July's regular Benicassim festival was less profitable than in previous years and its other key event, the British folk-based Hop Farm Music Festival, had weaker than expected sales.

Benicassim, which has taken place since 1995 near the town of the same name on the Spanish coast near Valencia, has become a mainstay of the European summer festival calendar, with the Stone Roses, Bob Dylan and New Order headlining in 2012.

Tickets have already gone on sale for the 2013 event. The company could not immediately be reached for comment as to whether it would go ahead.

Music Festivals Plc, which also runs the smaller London-based Irish music Feis Festival and new Spanish rock festival Costa de Fuego, is headed by Vince Power, founder of London music venue The Mean Fiddler.

It listed on London's junior investment market, AIM, in 2011, when it recorded pre-tax profits of 796,000 pounds on sales of 13 million.

"The board has in recent weeks pursued a number of different funding proposals but the company has not been able to procure the necessary funding it requires," Music Festivals said on Friday.

"Whilst the board considers the next steps it has requested that trading in its ordinary shares is suspended and a further announcement will be made in due course."

The European economic downturn and unemployment, particularly among festivals' key youth demographic, have hit ticket sales hard.

In Britain, a clash with the London Olympics has also been blamed for festival woes. August's The Big Chill and heavy metal festival Sonisphere Knebworth were both canceled in 2012, while new festival venue London Pleasure Gardens went into administration in August just weeks after it opened.

(Reporting by Rosalba O'Brien; editing by Kate Holton)