LITTLE ROCK, Ark. (AP) - It will be a while before U.S. 63 between Jonesboro and Crittenden County attains an interstate highway designation.

The Arkansas Highway and Transportation Department said Thursday the project to convert U.S. 63 to a four-lane divided highway with controlled access is complete.

Plans call for the highway to be designated as Interstate 555, but doing so isn't within the agency's four-year plan.

If the highway department were to convert the highway to an interstate, farm vehicles would not be able to use the highway. A segment between Marked Tree and Payneway needs a service road.

The service road would cost about $25 million, of which the highway department has about $3 million. The agency is considering whether to apply the funds to design or to build part of the road.

(Copyright 2012 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.)