The Federal Communications Commission on Thursday approved a measure mandating that companies such as AT&T and Verizon let smaller telecommunications carriers use their networks for mobile Internet service, a practice that is now voluntary.

The FCC vote was, however, divided along party lines, with three Democrats voting for the measure and two Republicans voting against it, according to a Bloomberg report.

Major mobile carriers are already required to forge agreements with smaller rivals for voice data, and the addition of Web traffic is essentially an extension of that rule, the report said.

Both AT&T and Verizon, the two largest cellular operators in the U.S., opposed the measure, Bloomberg said.

"Consumers expect mobile data services that will allow them to remain connected wherever they go; a data roaming rule will help ensure that consumers' services are not interrupted and that coverage is available on a competitive basis," the FCC said in a statement on the new rule.

"The widespread availability of data roaming arrangements will allow consumers with mobile data plans to remain connected when they travel outside their own provider's network coverage areas by using another provider's network. This promotes connectivity and nationwide access to mobile data services such as email and wireless broadband Internet access."

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-- Nathan Olivarez-Giles

twitter.com/nateog