A contract for British energy company Centrica for liquefied natural gas from Qatar is necessary to ensure energy security, the British energy minister said.

Centrica announced Wednesday it signed a four and a half year contract to purchase as much as three million tonnes of liquefied natural gas (LNG) a year from Qatar.

“Long-term deals of this kind with reliable suppliers like Qatar are vital for our future energy security,” British Energy Minister Michael Fallon said in a statement.

The $7bn deal could secure the energy needs of 13% of British households each year.

“It is vital that the UK has a diverse range of sources of supply to meet its energy requirements,” Centrica Chief Executive Officer Sam Laidlaw said.

The British economy imported 32% of its oil needs in 2012, up from the 25% reported for 2012. Gas imports should increase from 49% in 2012 to 53% in 2020.

Most of the British imports of LNG come from Qatar. The country relies on natural gas imported through pipelines from Norway and the Netherlands for the bulk of its imports.