Actividades de Construccion & Servicios (ACS), Spain's biggest construction firm by revenue, said yesterday it will not take a decision on making a further investment in Iberdrola, the utility that owns ScottishPower, until after the Spanish election. Spain goes to the polls on March 9.

ACS has diversified away from Spanish construction in recent years to shield itself from a slowdown in residential building and is now a major player in the country's energy sector.

ACS already has a stake of more than 7% in Iberdrola, plus an option for 5.2% more. Earlier this month, ACS said it had held talks with French utility EDF about making a joint bid for Iberdrola, Spain's second-biggest energy firm.

Iberdrola has said it will fight off any takeover attempt from EDF and ACS or any other predator. E.ON, the German energy firm, is also rumoured to be considering a bid for Iberdrola, having failed last year to buy the Spanish electricity company Endesa.

ACS posted a net profit of 1.55bn, a 24% increase over the previous year that was fuelled by its investment in power firm Union Fenosa. Sales rose to 21.3bn from 13.9bn in 2006 while earnings before interest, tax, depreciation and amortisation (EBITDA) rose 186% to 3.49bn, the company said.

Union Fenosa, in which ACS has a stake of just over 45%, contributed 2.1bn to the builder's EBITDA without which it would have risen just 13.2% in 2007.