Pennsylvania Gov. Tom Corbett is asking for help from the White House to end a strike by railroad employees that halted service Saturday morning on commuter trains in and around the Philadelphia region.

Corbett asked President Obama to authorize an executive order to create a Presidential Emergency Board, a directive similar to one he signed in March involving the Long Island Rail Road in New York.

The order would restart labor negotiations and train service which came to a halt at midnight, after union workers and transit officials with the Southeastern Pennsylvania Transportation Authority failed to reach a new contract agreement.

The unions, which represent about 450 workers, have been working without a contract for more than three years. SEPTA had offered $3-an-hour pay increases which aren’t retroactive to the end of the last contract.

The commuter rail line, serving five counties, has about 126,000 riders during peak travel times. The strike doesn’t affect subway or bus service.

“I have requested federal intervention from the president to immediately mediate the ongoing dispute between SEPTA and the engineers and electricians unions,” Corbett said Saturday. “It is imperative that parties continue to work toward an agreement.”