The huge £15m, 17-storey City Quays 3 building looks set to be built by construction giant Farrans.
The building, located at Belfast Harbour, is the latest and largest of the City Quays office schemes in the docks area, which could create 600 construction jobs.
The firm’s Darrell McGuckian said: “Farrans are delighted to be working with the Belfast Harbour Commissioners team to deliver the City Quays 3 project as part of their ongoing developments.
“We look forward to continuing our collaboration with Belfast Harbour Commissioners once again and to bringing this wealth of experience and expertise to the fore on City Quays 3.”
As the development is deemed a “regionally significant” project, it needs the final green light from Stormont to get the go-ahead.
Belfast Harbour unveiled record results last month, reporting a 5.6% surge in operating profits to £34m.
The Harbour also saw turnover rise by 6.5% to £61.9m during 2017.
Throughout the course of the year, £42m was invested by Belfast Harbour in new port facilities and regeneration developments.
Work is under way on a 900-space car park, while next year’s results are likely to see a further uplift in revenue, due to the new AC Hotel and films studios on the North Foreshore.
“A key factor in the success of Belfast Harbour is the ongoing growth in port throughput in sectors such as aggregates, steel, animal feeds and grains, roll-on/roll-off freight, ferry passengers and cruise ship visits,” said Joe O’Neill, Belfast Harbour’s chief executive.
“The harbour’s real estate activities also are delivering ongoing growth.”
Overall, port operations make up around 80% of overall turnover at Belfast Harbour.