The country's top four wireless operators and several regional carriers have all met separately with the FCC in recent days to plead their case on mandated data roaming ahead of the agency's vote on the issue next week.

Ex parte documents filed with the FCC show that Sprint, Leap Wireless International, MetroPCS, Cellular South and the Rural Telecommunications Group met separately with FCC officials this week to lobby their support for the agency's proposed data roaming mandate. T-Mobile conducted its lobbying by phone.

The long-awaited mandate goes up for a vote at the FCC's April 7 open meeting next Thursday. The order would create roaming agreements for mobile data similar to current agreements for voice services.

"Data roaming is a necessity both for carriers such as MetroPCS to compete more effectively with nationwide carriers and for customers and essential for potential customers to enjoy the ability to use both voice and data services over their mobile devices when they travel outside of their home carrier's network," MetroPCS representative Carl Northrop wrote in an ex parte filing.

Tier 2 operators and regional carriers say they need the regulations to stay competitive as mobile data services become increasingly important to their subscribers. AT&T and Verizon are the only two wireless operators to oppose the measure.

AT&T and Verizon Wireless also met with FCC officials this week in an attempt to dissuade the agency from moving ahead with mandated data roaming agreements.

Verizon said it has entered into data roaming agreements and said that the record "supplies neither a factual nor a legal basis" for the FCC to adopt a data roaming mandate, an argument it has previously presented to the agency.

AT&T restated its claims that an FCC mandate for data roaming agreements was unnecessary. "Wireless providers already have scores of data roaming agreements with more currently under negotiation and that they are aggressively investing in and deploying next-generation wireless networks," AT&T representative Jeanine Poltronieri said in a filing.

The FCC's data roaming order is viewed as likely to pass next week with support from agency Chairman Julius Genachowski. The agency also plans to vote on pole attachments, right of way issues for cell sites, network reliability standards, cell phone signal boosters and the video relay service program.