The pair say the move will enabling them to deploy Internet of Things and other technologies quickly and securely.
BT Division X, Enterprise MD Marc Overton, said the British company was working with Sweden's Ericsson, a leader in 5G technology, both in deploying and operating the networks, and in putting applications.
The partners have already worked together on several major projects incorporating private 5G networks, including Belfast Harbour in Northern Ireland.
They have installed a 5G private network across 35 acres of operational port, driving operational efficiencies and optimising processes across transport, logistics, supply chain and shipping, he said.
"We're now into phase two of the project and this includes various use cases such as teleoperation of heavy plant machinery, artificial reality (AR) for remote maintenance, as well as enhanced video AI analytics and the use of drones for surveillance and inspections," Overton said.
Under the new deal, the partners will focus on deploying 5G technology in sectors including healthcare, manufacturing, transport and logistics, sites such as large shopping centres or stadiums, and ports.