Urbis already gets �1m from the council each year

The �30m museum - the centrepiece of Manchester's Cathedral Quarter - already receives an annual �1m subsidy from the city's funds.

Urbis has failed to reach its target of 200,000 paying visitors in its first year, despite the massive influx of visitors last summer during the Commonwealth Games.

Liberal Democrats say the subsidy is "unacceptable", but the council leader argues it is worth investing more cash in Urbis.

In March the museum's boss, Elizabeth Usher, stepped down, despite being in the job for just eight months.

Simon Ashley, leader of the Liberal Democrat opposition at Manchester Town Hall, said the council should be spending its money on more important projects.

We would prefer to see the money spent improving our schools, cleaning our streets, and other issues that matter to the people of Manchester Simon Ashley, Liberal Democrats

"A �1.5m annual subsidy is unacceptable," he told BBC News Online.

"Like most people, we would prefer to see the money spent improving our schools, cleaning our streets, and other issues that matter to the people of Manchester."

He added a "radical" solution is needed to end Urbis' woes, suggesting a new visitor's centre for the city could be based at the museum.

But council leader Richard Leese said Urbis had earned the extra investment.

"Urbis is stunning," he said.

"It represents the cutting edge spirit of Manchester.

Urbis is a vital marketing tool in the future promotion of Manchester and it is well worth increasing our investment to further boost its work Council leader Richard Leese

"It is outstanding, futuristic and instantly recognisable. And at the same time it fuses so well with our history and heritage.

"Urbis is a vital marketing tool in the future promotion of Manchester and it is well worth increasing our investment to further boost its work."

He said thousands of people had enjoyed Urbis since it opened, but recognised more needed to be done to increase visitor figures.

Last month Ian Simpson, the Manchester architect who designed Urbis, criticised the contents of the landmark.

He said the attraction should have free admission, and the space should be better used.