New Zealand Oil and Gas believes it made a fair offer to takeover Cue Energy despite an appraisal report indicating the oil explorer should be offering at least 17 to 51 percent more.
The company was offering 10 Australian cents a share, valuing the ASX-listed Cue at A$69.8 million.
Cue's board had already recommended shareholders reject the offer saying it was too low.
A report by Grant Samuel said a fair price was between 11.7 and 15.2 Australian cents per share, valuing Cue at A$82 to A$106 million.
New Zealand Oil and Gas has responded with a supplementary report saying Grant Samuel's valuation contained errors and omissions.