American access to the Panama Canal, one of several new directives outlined in what amounts to a major overhaul of US strategic priorities, according to a new memo that was sent to senior leaders and reviewed by CNN.

The U.S. acquired the rights to build and operate the canal in the early 20th century. In a treaty signed in 1979, during the administration of Democratic President Jimmy Carter, the U.S. agreed to turn over control of the canal to Panama at the close of 1999.

The U.S. government has ordered the military to prepare plans for increasing its presence in Panama. This decision is part of a broader effort to secure control over the Panama Canal, one of the most important waterways in global trade.