President Daniel Ortega warned Costa Rica that Nicaragua may ask the International Court of Justice to restore to Managua a province he said it lost to "occupation" in 1824.

Ortega was referring to Guanacaste province, which is about 20 percent of neighboring Costa Rica's territory and a popular tourism hub.

"Costa Rica did not win that territory in an international court, but rather by force, with arms," Ortega said at a military ceremony on Monday.

He said he would like to negotiate with San Jose over the issue, an idea that has been rejected by Costa Rican President Laura Chinchilla.