DAJABON, Dominican Republic (AP) — The Dominican Republic’s president announced Thursday he would close all borders with neighboring Haiti starting Friday in a dispute over a canal on the Haitian side that would use water from a river along their frontier.

President Luis Abinader said air, sea and land borders would close at 6 am local time Friday and would remain shuttered “until necessary,” signalling that last-minute talks between the countries had failed to head off the closure. It is a rare move for the Dominican Republic, and could hit economies in both countries, though it will be most acutely felt in Haiti.

The closure is a response to the excavation of a canal by a farming group on the Haitian side that targets waters from the Massacre River, which runs along the border shared by the two countries on the island of Hispaniola.

The International Crisis Group said work on the canal had been suspended since the July 2021 assassination of President Jovenel Moïse, and that it resumed based on inaction by the Haitian government, “which has failed to respond to the problems created by the drought in the agricultural area of the Maribaroux plain.”

The organization has seen no evidence “that suggests there are any major politicians or powerful businesspeople behind it, as the Dominican government has claimed,” according to Latin American and Caribbean consultant Diego Da Rin.

Abinader in recent days suspended issuing visas to Haitians and closed the border near the northern town of Dajabon, paralysing a key economic lifeline for Haitians who buy and sell goods there several times a week. Those who live in Haiti but work in the Dominican Republic also cross the border daily.

“They are suffering a lot here in Dajabon, and in Haiti, too, because there are a lot of goods that are spoiling,” said Haitian businessman Pichelo Petijon. “There are millions of dollars in losses.”

Abinader accused Haiti of trying to divert water from the Massacre River, and said it would affect Dominican farmers and the environment. The river is named after a bloody clash between French and Spanish colonizers in the 1700s, and it also was the site of a mass killing of Haitians by the Dominican army in 1937.

On Wednesday, Haiti’s Ministry of Foreign Affairs said it was meeting with Dominican officials in the Dominican Republic to talk about the situation. The Dominican government said Thursday that the meeting had stretched into its second day but provided no details. The meeting was continuing when Abinader announced he would close all borders starting Friday.

Meanwhile, Jean Brévil Weston, leader of a farmers’ group near the border, was quoted by Haiti radio station Magik9 as saying that he will not stop working on the canal.

“It’s the canal or death,” he was quoted as saying. “We are ready to be buried by the canal.”

Haiti’s government issued a statement after Abinader’s announcement saying it would always favor dialogue, noting it was underway and “on a good track” when the president took “unilateral action.”

The government added that it would do what is needed to ensure the irrigation of the Maribaroux plain.

“The Republic of Haiti can sovereignly decide on the exploitation of its natural resources,” it said. “The government … will take all necessary measures to protect the interests of the Haitian people.”

Claude Joseph, Haiti’s former prime minister and an aspiring presidential candidate, said the excavation does not violate any agreements or treaties between the two countries, and urged workers to keep working on the project. Joseph previously clashed with Abinader over an unrelated issue, prompting the Dominican president to ban him from his country.

Abinader on Thursday also announced bans for nine other Haitians, the majority former government officials and one person he claimed was responsible for backing the canal project.

A line already was forming Thursday at the Dominican border town of Dajabon, with hundreds of people seeking to cross into Haiti for various reasons, many with heavy bags balanced on their heads or suitcases in hand. Dominican authorities were opening the gate only three times a day, and only for crossings into Haiti.