Church leaders today warned some of the region's best-loved buildings would struggle to be maintained, if the government pressed on with plans to tax restoration work.

The dean of Norwich, the Very Rev Graham Smith, said the maintenance of Norwich Cathedral, voted Norfolk's favourite building, would be jeopardised if chancellor George Osborne introduced VAT to the restoration of churches and cathedrals.

If the tax is introduced, ending VAT relief, costs will soar by 20pc.

The Very Rev Smith said: 'To effectively put another 20pc on the costs would mean that we would do less maintenance.

'The buildings would fall into disrepair.'

He claimed that the imposition of the tax would not mean the government got more money, but would result in less maintenance of historic buildings.

The dean, who returned from a 10-week trip to Zimbabwe on Saturday, where he met the bishop of Harare, said: 'It is an extremely important issue. The question of maintaining cathedrals is of national importance, never mind religious importance.

'We have this magnificent heritage which is part of our national identity. To Norfolk people it is of enormous importance.'

It costs �3,700 a day – �1.35m a year – to keep Norwich Cathedral open, without including major repairs, which the dean said run into an additional six-figure sum most years.

Much of the work is funded through volunteers at the Friends of Norwich Cathedral, but the dean argued that people would be put off donating money, knowing that 20pc of it would go to the government.

Norwich's vice-dean Jeremy Haselock and the dean co-signed a letter in yesterday's Sunday Times, with 21 other deans from cathedrals across the country, urging the chancellor to drop the plans.

In the letter they argue that paying VAT would 'seriously jeopardise the sustainability of our great buildings'.

The deans also question how the tax on alteration work fits in with the government's 'big society' agenda, when much of the restoration and maintenance work is done by volunteers and charities.

The letter reads: 'Cathedrals –like so many churches and community buildings that will be affected by this change – rely on the generosity of charitable trusts and private donors, as well as volunteer fund-raising, to keep their fabric in good repair and fit for purpose in today's world.

'Our listed status controls the quality of the materials and the craftsmanship we use.

'Raising a further 20pc on top of these already elevated costs is likely to prove unmanageable.'

The tax introduction on restoration work was announced in Mr Osborne's budget and has also provoked criticism from the National Trust, which fears that homeowners living in listed properties would face rising bills.

The deans added: 'We sincerely hope that the chancellor, George Osborne, will allow the present consultation to reshape his thinking on his VAT proposals, and decide to change his policy to one that will support rather than damage our nation's heritage.'

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