THE HAGUE, Netherlands (AP) — A U.N. court rejected Argentina's claims Tuesday that a Uruguayan pulp mill is pumping dangerous pollution into the river on their mutual border, angering Argentine protesters who have waged a three-year campaign against the mill.

The dispute over the mills has soured normally friendly relations between the countries, with Argentine protesters blockading a key bridge over the river.

Uruguayans hoped that the court ruling would lead quickly to the reopening of the international bridge between Guayleguachu, Argentina, and Fray Bentos, Uruguay. But activists blocking the bridge Tuesday reacted angrily to the verdict and vowed not to give up their fight, raising the possibility of a violent confrontation if Argentine police intervene.

Watching on a big screen beside their roadblock, many shouted and cried, complaining that the court let them down.

The verdict could affect billions of dollars in future development projects. The court said both countries "have a legal obligation" to work closely together in honoring their treaty requiring shared decision-making for projects affecting the river.

Presidents Jose Mujica of Uruguay and Cristina Fernandez of Argentina will meet soon to discuss how to follow through on the verdict, which both countries said they would respect.

Mujica made no immediate comment, in keeping with his effort to reduce passions and resolve the dispute, but his foriegn minister, Luis Almagro, called the verdict a reaffirmation of international law and the jurisdiction of a bi-national commission that manages river issues.

"In environmental politics, Uruguay follows the most strict international standards," Almagro said.

Fernandez made similar statements when asked about the verdict during her trip to Venezuela.

"Surely both of our countries are going to pursue from now on a strong monitoring effort, a strong control, because everyone — Uruguay, Argentina, and I believe every country in the region, what we really want is peaceful relations, and really to not create questions that initiate conflicts."

The International Court of Justice ruled that Uruguay should have involved the commission to inform Argentina of plans to build two pulp mills on the Uruguay River before authorizing construction, as called for in their 1975 treaty regulating the river's use.

It rejected Argentina's demand for compensation, however, saying that its reprimand to Uruguay "constitutes appropriate satisfaction."

"Ordering the dismantling of the mill would not, in the view of the court, constitute an appropriate remedy," the court's Vice President Peter Tomka said.

Argentine Foreign Ministry legal adviser Susana Ruiz Cerutti said in The Hague she was pleased that the court upheld the principle that "unilateral projects done without consulting won't be possible."

The court said Argentina provided no conclusive evidence that discharges from the $1.2 billion Finnish-built Botnia mill, which started work in 2007, have "caused harm to living resources or to the quality of the water of the ecological balance of the river."

Uruguay insisted at hearings in September that the mill meets strict environmental standards. But lawyers for Argentina said it is already pumping pollution into the broad river and releasing foul-smelling gas into the air.

The World Court earlier refused to order a halt to construction of the mills and turned down a Uruguayan request to order Argentina to end the bridge blockades.

The court, which is the highest judicial body of the United Nations, adjudicates disputes between nations. Its rulings are final and binding, though they are not always obeyed.

Scientists have lamented that Argentina and Uruguay have not done more to reduce river pollution from other sources, despite their long political battle over the paper mill.

Uruguay's arguments in favor of the mill were based in part on studies paid for by the Botnia paper company, and accepted by the national environmental agency, which found the plant has no measurable impact on the surrounding air and water or plant or animal life.

The paper mill is located far downstream along the Rio Uruguay, which runs for 1,100 miles (1,800 kilometers) from Brazil to the Rio de la Plata, and drains about 210,000 square miles (339,000 square kilometers) of farmland, an area larger than California and more than twice the size of Britain.

The agricultural runoff from this watershed likely includes vast amounts of fertilizer — including nitrogen, phosphate, potassium and magnesium, which combines with heavy metals from factories — mostly on the Argentine side — and untreated sewage from most of the nearly 100 Argentine and Uruguayan municipalities.

Juan Carlos Villalonga, campaign director for Greenpeace-Argentina, said both countries need to develop shared rules for paper mills and other factories along the river, where fast-growing eucalyptus trees promise a booming industry.

"This is a conflict that involves a lot of hypocrisy," Villalonga said. "There hasn't been a serious and ongoing evaluation of pollution in the river, neither in Uruguay nor in Argentina."


Associated Press Writers Michael Warren and Almudena Calatrava in Buenos Aires and Raul Garces in Montevideo contributed to this report.