Concerned by weaker economic growth, the central bank of oil-rich Norway has cut its key interest rate to its lowest level ever, 0.75 percent, and hinted that it could reduce it further.

Norges Bank said Thursday that growth was likely to remain low "for a longer period than projected earlier" because of weak oil prices and that oil investments were expected to fall further.

It also said that lower demand for goods and services from the energy sector would hit other parts of the economy and increase unemployment.

On the bright side, the bank mentioned a weaker currency would encourage exports and help domestic companies compete with importers.

Central bank Governor Oeystein Olsen said the outlook "suggests the key policy rate may be reduced further in the coming year."