The site already has planning permission and the facility could be complete by late 2027 or early 2028.
Moving the cruise berth will also free up space to expand the harbour’s existing marshalling area for wind turbines.
Mr O’Neill said there were increased opportunities in the sector with some major offshore wind farms being planned off the Irish coast.
“We envisage about 30 different windfarm projects over the next 10 years or so in our natural trading hinterland,” he said.
“We’ve got some existing capacity but we want to enhance that.”
Investment by the harbour is currently funded from its retained earnings, rather than by borrowing money.
It wants to borrow to invest in larger projects but is currently constrained by its legal status.
It is classified as a public corporation, meaning that any debt it takes on counts as part of Stormont’s capital budget.
It wants to be reclassified as a private corporation which requires legal changes, including reducing the role of the Infrastructure Minister in appointing the harbour board.
A change to the law in Scotland has allowed similar legal reclassification of ports there.
The Department of Infrastructure has launched a consultation, external on the issue.
