By Sarah Morland

The Dominican Republic is ready to restart a decommissioned canal off a river shared with neighboring Haiti, it said on Thursday, weeks after shutting down the border to stop another canal being built on the Haitian side that it asserts violated a treaty.

Santo Domingo shut its border in mid-September, cutting off movement of people and commerce through land, air and sea, citing the construction by private parties of a canal off the Massacre River on the Haitian side of the border in the area of Dajabon.

On Thursday, the Dominican government said its INDRHI water authority had completed tests of three motor pumps installed at the intake site and the La Vigia canal, decommissioned in 2007, was ready to resume operations in Dajabon.

"This immediate solution will guarantee water for local producers who could be affected by the construction of a canal in Haitian territory that diverts the waters of the Dajabon River," the government said in a statement.

Haiti, facing a humanitarian crisis driven by gang wars, has said that under the treaty it has the right to exploit resources on its side of the border. The countries have tense relations with the Dominican Republic deporting tens of thousands of migrants back into Haiti.

Dominican President Luis Abinader, who is seeking re-election next year, has also said his country is planning the construction of two dams that "without the treaty could significantly affect" Haiti.

The Organization of American States has called for a resumption of dialogue saying the current situation benefits neither party.

"There can be no doubt that Haiti and the Dominican Republic have equal rights of use over the Dajabon or Massacre River and that its water resources are vital for both, given the needs of its inhabitants, especially in the current context of drought," the OAS said in a statement last week.

(Reporting by Sarah Morland; Additional reporting by Paul Mathiasen; Editing by Richard Chang)