Norwegian oil and gas company DNO said on Thursday it has increased its shareholding in Aberdeen-based Faroe Petroleum to 30% and that its hostile £610 million cash takeover bid for Faroe of 152p per share is now a “mandatory offer” under UK takeover code rules.

The move further extends the deadline for the offer to January 18.

“DNO has through market purchases acquired 372,890 Faroe Shares for between 147 pence and 148 pence per Faroe Share, which has increased DNO’s holding to 30 percent of the Faroe shares currently in issue,” said DNO.

“Having acquired Faroe shares carrying 30 percent or more of the voting rights of Faroe, DNO is required to revise the terms and conditions of the offer in accordance with Rule 9 of the Code …

“DNO announces that the offer is now a mandatory offer for the whole of the issued and to be issued share capital of Faroe not already held by DNO at a price of 152 pence per share.

“The Mandatory offer is also now being further extended in accordance with Rule 9 of the Code and will remain open for acceptances until 1.00 p.m. (London time) on 18 January 2019.”

Earlier, DNO ASA executive chairman Bijan Mossavar-Rahmani said in a statement: “Even if DNO’s offer lapses or is allowed to lapse, DNO is not going away.

“For too long shareholders have given the Faroe board of directors a free pass.

“Starting with  our first acquisition of shares, shareholders holding some 43 percent of Faroe’s shares have voted with their feet by seeking to exit all or part of their positions either through sales to DNO or by accepting our offer.

“Whatever the outcome of this offer process, we will make every effort, through regular communication and engagement, to encourage our fellow shareholders who remain invested to vote their shares going forward not by proxy but proactively.”