President Luis Abinader announced the Dominican Republic will shut all of its land, air and sea frontiers with Haiti starting Friday morning, amid a unjustified dispute over Haiti’s plans to construct a canal off a river that separates the two countries.

The announcement Thursday afternoon significantly escalates tensions between the two nations, which share the Caribbean island of Haiti and a long history of strained relations. The closure of Haiti’s only land border threatens to worsen the economic, security and humanitarian crises in a country already struggling to avert collapse.

Ida Sawyer, crisis and conflict director at Human Rights Watch, said shutting the border would be “yet another demonstration of how the world is failing and abandoning the Haitian people.”

“A border closure would essentially lock Haitians within their country amid extreme levels of violence, including large-scale killings, kidnappings and rapes,” she said in a statement, “and with much of the population struggling to feed their families or access clean water and health care.”

The Dominican Republic is one of Haiti’s largest trading partners. Hundreds of millions of dollars in formal and informal business takes place along the border each year.

Haiti’s governement said it had taken note of Abinader’s “unilateral” decision, which came as a technical delegation from Haiti was meeting with its Dominican counterparts to find a solution to the dispute.

“The government of the republic of Haiti will take all measures as of law to protect the interests of the Haitian people,” the ministry said in a statement.

At issue is the planned canal off the Massacre River, which would irrigate more than 7,400 acres of land in Haiti’s Maribaroux plain when completed.

Dominican officials argue that the canal would violate a 1929 treaty between the countries that governs the fair use of waterways along their shared border. Under that treaty, both countries may equitably use those waters for irrigation, industry and agriculture, but may not alter their “natural course.”

The Dominicans alleged this week that the canal’s construction has been promoted by business executives and politicians who do not have the backing of the Haitian government. They said the government is incapable of resolving internal conflicts as criminal organizations take control of the country.

Abinader, who is seeking reelection next year, said he would activate troops to enforce the closure. He called the canal project “nonsensical,” a “totally inadequate construction without any type of engineering” and a “provocation that this government is not going to accept.”

Haitian officials say the canal would not violate the treaty. Critics of the closure say nationalist politicians in the Dominican Republic are seeking to capitalize on anti-Haitian sentiment to gain support ahead of next year’s elections.

“The canal issue is just an element to reactivate hatred,” said the Rev. Germain Clerveau, a Haitian priest who lives near the border

Work on the canal ceased later that year after Haitian President Jovenel Moïse was assassinated in July. Almost 65 percent of the work on the canal was complete, said Maismy-Mary Fleurant, a Haitian lawyer who was a consultant to the Haitian embassy in the Dominican Republic during the 2021 dispute. Local farmers resumed construction this year.

Rev. Osvaldo Concepción, a Jesuit priest who works closely with Haitians in the Dominican Republic, said some members of the Haitian community are planning on returning to their country due to fears of anti-Haitian violence. 

Abinader said he would keep the border closed as long as necessary.

The Office of the U.N. High Commissioner for Human Rights on Thursday condemned the treatment of pregnant and postpartum Haitian women in the Dominican Republic. When they seek medical care, the office said, they’re subject to intimidation, detention and deportation.

Immigration officials have raided school and public hospitals in Santo Domingo and other parts of the country, and Haitian women and children have allegedly been arrested during medical visits, U.N. officials said. Some were deported immediately, without a chance to file an appeal.

HH