Too many artistic treasures are gathering dust in store rooms, a councillor has claimed.

Green Party councillor Bill Randall said Brighton and Hove had a "very decent" fine-art collection but only a small part of it was displayed at any one time.

He has called on the city council to investigate the possibility of constructing a purpose-built public gallery or creating a new one within an existing building.The city owns an impressive collection of 1,504 oil paintings - half the publicly-owned paintings in Sussex - and many more watercolours, prints and drawings.

But most of the pictures lie hidden from view awaiting their turn in the spotlight. Those which are on display are scattered across the city in different buildings.

The Virgin And Child by Nicholas Poussin is on show at Preston Manor while Christ's Entry Into Brighton by John Upton, which depicts Christ flanked by Sixties figures including Jimi Hendrix, Cassius Clay (Muhammad Ali), Christine Keeler and Harold Macmillan, hangs in a seminar room at the University of Sussex.

The most famous painting in Brighton Museum and Art Gallery is The Raising Of Lazarus by Jan Lievens, which once hung in Rembrandt's house.

Others are on display at Hove Museum and Art Gallery.

David Beevers, keeper of the city council's fine art, said: "At any one time, we have between 250 and 300 paintings on display but there are many more we don't have room for and that has always been the way."

Brighton Museum and Art Gallery was transformed three years ago in a £10 million redevelopment which managers said has greatly improved access to the city's fine-art collection.

Despite the modernisation and although it is normal practice to rotate a collection to protect the paintings and sustain visitors' interest, Coun Randall said he would pursue the idea of a separate gallery to cement the city's reputation as one of the UK's leading artistic cities. He said: "I firmly believe a city with Brighton and Hove's cultural aspirations should have a separate art gallery to complement the splendid museum.

"Only a small part of the very decent art collection can be shown at one time. A new gallery would make more of the pictures available to the public."

Pauline Scott-Garrett, the council's heritage director, said she would welcome a debate on the future of the city's art collection but the council had to be realistic. No gallery in the world displays all its art all of the time.

She said: "Of course, everybody would love to have more display room but at the moment we are working on creating better public access to our collections with what we have got."

Brighton-based broadcaster Simon Fanshawe, a member of the South East Arts Council, claimed the Green Party had opposed previous attempts to invest in the city's culture and said it was "a little bit rich for the Greens to start talking about the need for a new cultural facility".