Accusing Haiti of violating a 1929 treaty between both countries, he said that the Massacre River is a key resource for Dominican farmers and that construction could damage the environment, including a wetland.

“The precedent of an irrigation project built unilaterally can lead to an escalation of constructions that would destroy the river,” Abinader said.

The river is named after a bloody battle between French and Spanish colonizers, and it was the site of a mass killing of Haitians by the Dominican army in 1937.

The full border shutdowns came four days after Abinader announced that his administration had stopped issuing visas to Haitians and had closed the border near the northern town of Dajabon.

He said it was important to raise awareness in the international community so it comes to Haiti’s aid.

“There is no Dominican solution to Haiti’s problem,” Arbinader said. “We cannot be asked for more than what we already do.”

A spokesperson for the office of Haiti’s prime minister declined comment Sunday and referred to a Friday statement condemning Abinader’s decision to shutter all borders while both sides were meeting to find a solution. Haiti’s government has said it supports the canal project.

Haiti also has requested help to help quell a surge in gang violence, with the U.S. saying it would submit a UN Security Council resolution that would authorize Kenya’s offer to lead a multinational police force.

A resolution has yet to be submitted, and no timetable has been provided.