Argentina's President Cristina Fernandez, intent on increasing tension over oil exploration in the South Atlantic, has signed a government decree restricting the movement of vessels between the Argentine mainland and the Falkland Islands, also known as Las Malvinas."Every ship or vessel intending to transit between ports located on the Argentine mainland and ports located in the Malvinas, South Georgia, and South Sandwich Islands, or through Argentine waters toward the latter, and/or loading goods to be transported directly or indirectly between these ports must request prior authorization by the competent national authority," the decree stated.Fernandez's decree follows last we...