The Liberal Democrats are pressing for second home owners to pay a council tax "premium" to tackle the housing crisis.

An amendment is to be tabled to Government legislation that if approved could net the Westcountry, which boasts a large number of holiday homes, a financial windfall.

There are estimated to be 26,000 second homes in Cornwall and Devon. Critics argue they undermine year-round communities and force up house prices for local people.

The Second Home Premium has been proposed by Annette Brooke, Lib Dem MP for Mid Dorset and North Poole.

Her amendment to the Local Government Finance Bill has been signed by Stephen Gilbert, Lib Dem MP for St Austell and Newquay.

Mrs Brooke's constituency includes the coastal district of Purbeck, where the rate of second home ownership stands at more than 7 per cent.

She said: "In some areas there are very large concentrations of second homes in villages, and as a consequence the village starts to lose its facilities – bus services, and local shops and pubs. There is a case for intervention if a local authority wishes.

"There are practical problems with the implementation of such a policy but as Liberal Democrats we want to generate a widespread debate around these issues – and this is party policy."

The charge would be discretionary, but could be difficult to enforce as there is no simple way to check whether a home is used only some of the time.

The Government announced last year it is consulting on plans to remove the council tax discount on second homes, which ranges from 10 to 50 per cent, depending on the council.

Removing the 10 per cent discount in Cornwall should provide an additional £1.6 million to the council's coffers.

MPs say the extra cash should be used to underwrite affordable community housing and shore-up services.

Permanent residents in the most desirable coastal and countryside villages complain they turn into ghost communities outside of the summer season. But second home owners say they help buoy the local economy through spending in shops and restaurants and only place a modest burden on councils.

The Conservative party is less enthusiastic about a premium, but Lib Dems are anxious to make the most of the opportunity presented by scrapping the tax discount.

In an interview with the Western Morning News last year, Deputy Prime Minister Nick Clegg, the Lib Dem leader, made it clear the policy was still live. He said the party, with its roots in the South West, "knows what it's like when you've got communities where people can't get on the property ladder, not least because they've been outpriced by incomers from elsewhere".

The amendment, which calls for a "higher amount of (council tax) for second homes", will be tabled at the report stage as the Bill makes its way through Parliament.