ROME, Dec 15 (Reuters) - Italian Prime Minister Mario Draghi said on Wednesday that energy companies that have made profits may have to contribute to efforts to curb increases in bills for households and companies. With international energy prices continuing to rise, Draghi told parliament the government was ready to provide more funds if necessary to limit the increase in household energy bills, but said energy companies should also play their part. "It"s hard to imagine a structural solution that doesn"t consider the profits that electricity and other kinds of companies have made from the rise in gas prices," Draghi said. "It"s difficult not to call on the companies that have made these profits to contribute to (reducing) the costs."