Marape's comments come ahead of a national election in June.
Talks between local stakeholders and the PNG government look to have stalled, with a key sticking point for the K18.5 billion mining operation being the mine waste disposal system.
Morobe's provincial government prefers a tailings dam for mine waste, while the national government prefers dumping the tailings deep at sea via an up top 50km-long disposal pipeline.
In Lae last week, Marape acknowledged the different views and said a decision would not be made "until every party at the table is satisfied and their concerns have been heard" and "until a win-win consensus is reached".
A further development forum is planned in late on April 27.
The mere issue of development remains contentious. A coalition of PNG and Australian civil society organisations are calling on Newcrest and Harmony not to advance Wafi-Golpu until the Morobe communities are on board.
Open letters to various PNG ministers were dispatched from the Centre for Environmental Law and Community Rights, the Evangelical Lutheran Church of Papua New Guinea, Jubilee Australia, and Australia's Mineral Policy Institute
The letter requested a halt of any further approvals until discussions can be had with all affected project communities, including the 400,000 who live on the Huon Gulf.
Coastal communities are against the deep sea tailings disposal given the risk to fishing and the marine ecosystem, and the risk of spills in agricultural land from pipelines that will transport the mine waste to the coast.
The Wafi-Golpu copper-gold operation is expected to require five years to construct, and will produce some 360 million tonnes of tailings over three decades.
Jubilee Australia said deep sea tailings, which has been used at the Lihir gold mine since the 1990s, would not be permitted in Australia, and should not be permitted in PNG.
A special mining licence had been expected to be issued in 2019, but was delayed by the change of government, and then a challenge by Morobe to an environmental permit that was granted in 2020.
Average annual production over the 28-year mine life is set to be 161,000 tonnes of copper and 266,000oz of gold at C1 cash costs of just 26c per pound of payable copper, or negative $2128 per ounce on a gold all-in sustaining cost basis.