Belfast Harbour is playing down fears that its City Quays 3 development will fail to attract tenants as companies contemplate having more staff working from home in the long term.
The huge development of 250,000 square feet of office space is due to be completed next year, but there has been no announcement of any companies signing deals to move into the building.
"We believe that prospective tenants will continue to see the value in having high-quality office accommodation in which their people can collaborate, share ideas and interact safely," a spokesperson for Belfast Harbour said.
But the spokesperson added that Belfast Harbour, for commercial reasons, could not reveal whether any deals had been signed or if there were any ongoing discussions.
No public announcement of any deals have been made.
Concern over space is growing, particularly after it emerged that only 5% of workers have returned to their offices in Belfast, according to a survey by business representatives, and reports from Dublin that Google is pulling out of plans to rent more space in the city.
The tech giant was planning to move in to 202,000 square feet of space close to the city's quays to accommodate approximately 2,000 people but has confirmed that this will not happen, according to a report in the Irish Times.
One source told the newspaper that it was not a good time for companies to invest in commercial office space "while they are looking at what the future of work looks like".
But Belfast Harbour, which manages several office developments, said that City Quays 3 was on schedule for completion next year".
"Many of the current City Quays tenants already work a hybrid workspace model (a mix of office and home working) which will still have an office at its core supported by varying levels of home working, and we understand that this will be different for each individual occupiers' business needs," a spokesperson added.
City Quays "will be one of the largest Grade A office developments to be built in Northern Ireland supporting demand from international investors", according to the official documentation. It is estimated the cost of construction will be £50 million, with the building designed to accommodate 2,500 workers.
But latest reports reveal a sharp drop in the take-up of office space in Belfast. Lambert Smith Hampton said only 86,216 square feet were picked up in the first quarter of the year and only 25,000 in the second.
This was the lowest on record and a drop of 53% on last year, the property consultants reported.
A survey by Belfast Chamber recently reported that just 5% of office workers in the city centre were back in their offices. If this continues into the long term, economist Dr Esmond Birnie warned businesses could lose as much as £200 million a year.
The chamber is urging the Executive to work with businesses to return workers safely to their offices.