The race for Mexico's July 1 presidential election is becoming a street fight.

The two leading parties have agreed to debate about an unfinished roadway that the conservative National Action Party calls the Bridge to Nowhere.

But the two parties can't agree on where to meet. National Action says it should be at the part that's unfinished. The front-running Institutional Revolutionary Party wants to be at the part that's done.

President Felipe Calderon's National Action Party accuses poll-topping candidate Enrique Pena Nieto of lying about promises to build roads and other projects in the State of Mexico when he was governor.

Pena Nieto has complained about the attack campaign ads, and authorities say they will investigate.