Scottish Power said it is on track to meet its full-year targets

The energy giant said the electricity and gas price rises could be necessary due to current high wholesale prices.

Its warning came as the firm unveiled �329m ($574m) in third quarter pre-tax profits, up from �168m a year earlier.

Scottish Power, which last increased bills in October, said it was on target to meet its full-year figures.

Revenues for its third quarter to 31 December increased to �1.6bn from �1.3bn a year previously.

New boss

Back in October it increased both its gas and electricity bills, saying it had been hit by a 70% rise in wholesale energy costs over the previous six months.

The Glasgow-based company added that the sale of its US subsidiary PacifiCorp was proceeding well and should be completed earlier than its existing timetable of between May and November 2006.

Last month the firm appointed Philip Bowman as its new chief executive.

Australian Mr Bowman was formerly chief executive of drinks giant Allied Domecq.

Scottish Power both produces electricity from its own power stations and wind farms - its wholesale business - and supplies electricity and gas to consumers via its retail arm.

In November, it rejected a bid approach from German utility E.On which would have valued the firm at about �11.3bn.