NEW YORK (Reuters) - Rivals AT&T Inc and T-Mobile USA have agreed to open their networks to customers of the other company in New York and New Jersey where their services were hurt by power outages and flooding after Hurricane Sandy.

The companies said they had reached a network roaming agreement and that customers would not see any change to their current rate plans as a result of the roaming agreements.

Both operators use the same GSM wireless technology, which means that their phones can work on each other's network. T-Mobile USA is a unit of Deutsche Telekom .

(Reporting By Sinead Carew)