Responding to media reports on how these wells could affect its proposed merger with Anzon Australia, the company said detailed technical work is being carried out with Anzon's cooperation and Nexus expects to finalise its findings on reserves over the next two weeks.

Following this, further announcements will be made on revisions to the merger terms and timetable.

Nexus added it still believes a merger is in the interests of the two companies.

The Australian had reported on Wednesday that the terms of the deal between Nexus and Anzon would be substantially revised as the Basker-Manta field was not looking as good as previously expected.

It said the last drilling results "were not flash" and that Nexus was understandably keen to get a few facts before handing over 71c cash per share plus its own stock for Anzon.

Anzon's original Basker-6 appraisal well had failed to find a southeast extension of the Basker field after intersecting its objectives about 40m low to prognosis and below the hydrocarbon-water contacts, leading to suggestions that reserves at the field might be downgraded by as much as 40%.

While the subsequent sidetrack did encounter what appeared to be a southeast extension of the field, questions still remain about the two wells' cumulative impact on reserves at the field.

Basker-6ST1 is expected to start production in mid-July at about 1500 barrels of oil per day, according to project partner Beach Petroleum. Production from the Basker project currently averages over 10,000bpd.

Nexus and Anzon had in January this year announced they had agreed to a merger, which values Anzon at about $648 million or $1.75 per share, and comprises $0.71 in cash and $A1.04 in scrip for each Anzon share.