Norwegian oil company DNO ASA has achieved another slight increase to its stake in Faroe Petroleum, it said Jan. 4 as it continues its battle for control of the British business.

DNO's combined ownership and bid acceptances now stand at 43.8%, up from about 43% on Jan. 3 but still short of a controlling stake in London-listed Faroe.

It had previously required backing from 57.5% of Faroe shareholders to take control, but that fell to 50% on Jan. 3 after it lifted its holding sufficiently to turn the bid from voluntary to mandatory and thus subject to takeover regulation requiring a lower threshold.

Faroe separately reiterated its view on Jan. 4 that the 610 million pound (US$772 million) offer was inadequate, undervaluing the North Sea portfolio that DNO covets as it seeks to expand its operations, which are primarily based in the Middle East.

A report by oil industry analysts Gaffney, Cline & Associates, first released by Faroe on Jan. 2, valued the Aberdeen-based company's shares at between 186 and 225 pence, a premium of up to 48% on DNO's offer price of 152 pence.

RELATED: DNO Presses On With Faroe Petroleum Takeover Offer Despite Board Rejection

DNO's shares traded up 4% by 2:43 a.m. CST (8:43 GMT), supported by a 1.6% increase in the price of crude oil, while Faroe shares rose 0.5% to 154 pence.

Faroe shareholders have been set a Jan. 18 deadline to decide whether to accept DNO's bid. (US$1 = 0.7899 pounds)