It told US regulators that it had extended the dates in the contingent LNG project agreements with Mitsui and Energy World Corporation to "provide flexibility for partner selection and final investment decision".
Mitsui is to sign an agreement with InterOil for a condensate stripping plant, while Energy World Corporation is to sign an agreement with InterOil for an LNG plant.
Both agreements are conditional upon InterOil reaching the go-ahead for the project from the PNG government.
InterOil has been forced to alter its plans for the LNG project by the PNG government, which would prefer a "big name" come onto the project to operate a larger LNG plant than InterOil had originally planned.
It and joint venture partner Liquid Niugini Gas had secured approval from the government for a 3.8Mtpa LNG plant, fed by gas from the Antelope and Elk fields.
However, the pair still needs to complete an amended project agreement with the government and swing a deal with a partner the government approves of.
Meanwhile, InterOil has hit the largest single hydrocarbon column to date at the Antelope field, with Antelope-3 tapping a 701m column.
The well reached total depth on Christmas Day, and showed similar reefal reservoir characteristics to the offset Antelope-1 and Antelope-2 wells.
The third well shares the same water contact with the previous two wells.
The forward program is to run remaining wireline logs, before casing and suspending the well as a future producer.