US operators AT&T and T-Mobile USA have agreed to share their networks in New York and New Jersey in an effort to provide customers with adequate mobile service following the devastation caused by Hurricane Sandy.

The roaming agreement means voice calls and data will use whichever network is most operational or has spare capacity in a particular area. The networks are based on GSM and UMTS standards, meaning voice and data traffic can be shared across both networks.

The use of the different network will not impact the service agreements customers have with either operator.

Mobile services suffered following the hurricane with flooding, power outages and damaged equipment hitting the services of the operators.

In an update on the situation in north-east US the chairman of the Federal Communications Commission (FCC), Julius Genachowski, said the condition of the communications networks is improving although “serious outages remain” in the hardest hit areas.

He added that the FCC is continuing to work with the Federal Emergency Management Agency and other partners in the response effort. “The crisis is not over. We’ll continue to be intensely focused on helping with the full recovery of wired and wireless communications infrastructure,” he said.

In its latest statement, Verizon Wireless’ said its mobile network “performed well” following the hurricane due to the installation of permanent backup generators at most cell sites, allowing at least 94 percent of its towers from Maine to Virginia to be currently operational.

The US number-one operator’s network teams continue to work on restoring the sites that have been offline due to lack of power, mainly located in New York City and Northern New Jersey. Service has improved in Lower Manhattan and other parts of the Metropolitan area over the past 24 hours, the operator added.