(Sharecast News) - Norwegian oil producer DNO has acquired a further 32.25m shares in AIM-listed producer Faroe Petroleum after it upped its cash offer for the group to 160p per share after the close on Tuesday.DNO now owns or has acceptances for 195.52m Faroe shares, roughly 52.44% of the company's issued share capital - just short of the 57.5% needed by the Scandinavian firm.DNO intends to extend the offer, which effectively valued the firm at £641.7m, until 17 January despite the downturn in markets since its initial offer on 26 November.Faroe had insisted on multiple occasions that the offer was opportunistic and that it significantly undervalued the group, which, according to an independent valuation by Gaffney, Cline & Associates, had an implied valuation of 186p to 225p per share based on its $1bn of assets.As of 0820 GMT, Faroe shares had slid 0.13% 160.20p.