Emerald Express will run from New York, US, to Belmullet on the west coast of Ireland with a branch to Grindavík, Iceland. Future connectivity is also planned to Lisbon, Portugal.
Under the agreement, AT&T will provide facilities and operational support for terminating Emerald Express at the former TAT12/13 cable station in Shirley, New York.
Emerald said that this infrastructure would allow it to utilise the most innovative optical technologies and provide the most advanced undersea telecoms system constructed to date.
"As we continue towards full implementation of Emerald Express, we are extremely pleased and looking forward to a productive relationship with our strategic collaborators, including AT&T," said Dr. William C. Marra , CEO of Emerald Networks.
"Due to the continued market expansion of media and mobile demand for internet bandwidth and new multimedia applications we are anticipating massive market changes driven by explosive growth in telecommunications traffic worldwide, and our system will be part of this evolution."
The 5,200km Emerald Express project was announced in December 2011 and is expected to have a latency of less than 62 milliseconds in a round trip.
Emerald Express is scheduled to be ready for service by mid-2014.
