Centrica, the firm that sells the British Gas brand, has forged a landmark deal to import gas into the UK from mainland Europe.

Dutch gas firm Gasunie has signed a contract to deliver 80bn cubic metres of gas to the UK over a 10 year period, valuing the deal at about 8bn euros (�5.3bn).

The transportation route for the gas is still being studied, but is likely to result in an additional pipeline being built linking the UK to continental Europe.

Currently, there is only one such pipeline which links the UK's Bacton to Belgium's Zeebrugge.

The move represents the long-term trend of rising gas demand that will see the UK moving from a net exporter of gas to a net importer.

"This secures stable supplies for our customers for the foreseeable future," said Centrica's chief executive, Sir Roy Gardner.

"It is also good news for UK plc, encouraging development of additional transportation infrastructure to meet the nation's gas demand."

The UK is facing rising gas demand but dwindling North Sea supplies, leading to predictions of a future supply squeeze.

This has led the major energy firms to study long-term methods to import gas, including building liquefied natural gas terminals or new pipelines.

Gasunie said the transportation route for gas is still being studied but is likely to result in an additional pipeline being built.

The contract represents almost one fifth of Centrica's gas needs in the UK.

If follows a deal with Norway's Statoil last month that covers a further 10% of Centrica's needs.