Virginia Railway Express has missed a planned deadline for lowering the price of special tickets that encourage riders to take Amtrak instead of its crowded trains.

The commuter train service had said it planned to lower the cost of its step-up tickets from $5 to $3 starting Dec. 1, but it sent an apology to riders on Monday saying it likely won't happen until at least Jan. 1.

"Unfortunately, when we put out that original estimated date in October, things have not panned out that way," the service said in an email to riders. "Currently, we are still waiting for the funding agreements to be finalized by the Commonwealth of Virginia."

The commuter train service began subsidizing $5 of the $10 step-up tickets in May 2011 as a way to combat crowding on its commuter trains, which shuttle riders from as far as Manassas and Fredericksburg into D.C. With the additional ticket, VRE ticket holders can take an Amtrak train when crowding on VRE trains means standing-room-only trains. But due to ongoing crowding problems, the train service wanted to drop the price further.

An average of 400 VRE riders are taking advantage of the program, the service has said. The system averages more than 19,000 trips per day on its two lines.