NTT had expressed interest in developing the Lakeview site several years ago, QLDC chief executive Adam Feeley said.
"Their interest in the site is reasonably long-standing, but the specifics about what the proposal might be is relatively new," Mr Feeley said.
"We've got to the point where we understand roughly the amount of land they're looking for, the location where they would like to be, and at a very broad level the kind of commercial terms which might exist between us and them.
"They think it's a good opportunity, we think it would work well with the other developments being contemplated and we're now going to take the step to see if we can actually reach an agreement."
The council is also considering another recreational business opportunity for Lakeview with an as-yet undisclosed company.
The second company wanted to remain anonymous for commercial reasons, but it was potentially viable for both projects to be developed next to the convention centre, Mr Feeley said.
NTT southern regional general manager David Kennedy said NTT had carried out extensive customer research over several years into various site options for a hot pools development in Queenstown, which identified Lakeview as the preferred option.
The council has not formally resolved to develop a convention centre but is investigating the issues which will be taken into account in its decision next year. These include the best mix of uses, the site's zoning, the need for additional infrastructure, and the ownership of the land and facilities.
The master plan put forward for council consideration this week has three main elements: a convention centre and two commercial recreational operations along the frontage of Thomson St; a mix of commercial and residential areas at the back of the old Lakeview campground; and a market square.
Councillors will decide whether to authorise Mr Feeley to progress negotiations with NTT and other potential commercial developers, including Sky City, and report back in February.
A comprehensive report on financing and rating impacts for the project will be delivered next March.