"Visa delays continue, due in part to recent political uncertainty surrounding the appointment of a new government, and may continue to restrict the scale of drilling operations," Regency said last week.
Drilling started in late July while Regency is still awaiting the full results from the ground-penetrating radar work at the project completed in the previous month.
"Positive visual results and good depths of ore-bearing material from the drilling have been recorded, but no results will be announced until sample analysis results have been received from the laboratory," the London-based company said.
The exploration licence for the project covers 242 square kilometres and in 1999 Anaconda Nickel - led by Andrew Forrest before he founded Fortescue Metals Group and became a billionaire - estimated that a 158sq.km area held 630 million tonnes at 0.78% nickel and 200Mt at 1.01% nickel.
Meanwhile, Regency is also applying for a geothermal exploration licence in PNG (ELA 1953) and said no objections were raised during a recent hearing.
The Mambare project is a JV between Regency and private technology company Direct Nickel.
However, Direct Nickel is set to become an ASX-listed company through a reverse takeover of the failed Wintech Group.
A general meeting over a recapitalisation plan for Wintech, in which the company will be renamed Direct Nickel, is scheduled for September 2.
Regency expects to be offered shares equating to about 7% of the issued capital of Direct Nickel under the recapitalisation plan.
With help from CSIRO, Direct Nickel is advancing a game-changing technology for processing nickel laterite ores to yield superior economic and environmental benefits.
Direct Nickel chief executive officer Julian Malnic is well-versed in PNG and helped set up Nautilus Minerals in 1997.
Malnic was also the founder and chairman of Niugini Mining which discovered the Lihir gold deposit and he remains chairman of the Sydney Mining Club which he helped create in the ‘90s.
Direct Nickel plans to use its nickel processing technology at the Mambare project, along with other nickel laterite projects in the Asia Pacific and Western Australia.