The new terminal, which first came to light in October 2015, would be privately built.

The existing $750 million Hamilton Portside cruise ship terminal opened in August 2006, but two years later the need for a larger capacity facility was already being voiced.

The inability of Portside Hamilton, upstream from the Gateway Bridges, to accommodate larger vessels has seen larger ships dock at container yards at Fisherman Islands.

The proposed site for the new mega-cruise ship terminal was on the north bank of the Brisbane River at Luggage Point, almost directly opposite the Port of Brisbane's bulk terminal.

The agreement was foreshadowed in February, during a visit of the 347-metre Ovation of the Seas.

Port of Brisbane chief executive Roy Cummins said the agreement meant engineering and design work could be progressed, which would inform the final business case that would be presented to the state government.

"While this does not mean a final investment decision has been made, reaching these in-principle agreements was a key requirement of (the Port of Brisbane Pty Ltd) board to demonstrate the project's viability," he said.

Queensland Treasurer Curtis Pitt said the agreement with the state government, Brisbane City Council and Queensland Urban Utilities represented a "significant step forward" in the government's market-led proposal assessment process.

"Agreement on terms between the Port of Brisbane and key stakeholders has opened the way for the progression of the detailed business case," he said.

"Good progress has been made with these stakeholders to overcome hurdles and develop a facility that will bring a welcome economic boost and new jobs to our state."

Mr Pitt said the negotiations between the stakeholders had addressed issues such as road access to the site.

"In-principle agreement with these stakeholders means that realistic solutions have been developed and the way is now clear to undertake the detailed business case to finalise the Port's proposal to deliver a facility that will be a welcome addition to Brisbane's tourism infrastructure," he said.

"As a result, this now means we can progress engineering and design works."

Mr Pitt said a record 329 cruise ships visited Queensland in 2015-16, which was more than any other Australian state.

"The cruise sector already supports more than 2700 jobs in Queensland and we want to see this number grow because the cruise industry supports local businesses and sustains our regional communities," he said.

"The proposed new terminal will be able to accommodate the mega-ships now becoming widespread in the cruise industry.

"It's estimated that over 60 per cent of cruise ships in Australia will be longer than 270 metres by 2020."

Brisbane Lord Mayor Graham Quirk said his council had offered its "full support" for the project.

"An in-principal commitment of $5 million has already been made by council, for half of the costs of preliminary works to upgrade the local road network leading to the new terminal," he said.

"Council welcomes news that this $100 million investment in our tourism industry is one step closer to being completed."

If approved, the new terminal would be completed during the 2019-20 cruise season.