The London and Dublin-listed junior also said it remains in negotiations with an unnamed party or parties about possibly farming out some of its holding in the Ruvuma block off Tanzania.
Granting of an appraisal licence by Tanzanian authorities will see Aminex complete another round of seismic on the block as well as drill an appraisal hole at the Ntorya-1 discovery well.
The appraisal licence has a duration of two years with extension options.
The new seismic programme is anticipated starting in the autumn.
In May Aminex said it has secured consent from state oil company Tanzania Petroleum Development Corporation for a deferral of drilling due to be carried out during the first exploration period that expires at year-end until the second period expiring in late 2016.
The change to the terms of the Ruvuma production sharing agreement gave Aminex breathing space as it pursues ongoing talks with “a number of parties” for a farm-in deal on the block, where it currently holds 75% as operator with partner Solo Oil on 25%.
The block covers about 6000 square kilometres mainly onshore Tanzania, while also encompassing shallow-water sections and a deep-water part close to the coastline, and is estimated to hold around 178 billion cubic feet of discovered gas in place. Aminex estimates the potential for a total prospective recoverable resource of over 4 trillion cubic feet in all the prospects already identified within the block.