Independent directors of BW Energy have rejected a mandatory offer from parent BW Group and revealed the company could be delisted from the Oslo Stock Exchange.

BW Group launched the bid on Wednesday at NOK 27 per share, valuing the operation at NOK 6.7bn ($637m).

A letter from the oil exploration and production company’s board, excluding chairman and BW Group principal Andreas Sohmen-Pao and Marco Beenen, chief executive of affiliated shareholder BW Offshore, said directors had sought a fairness opinion from Pareto Securities.