onal Court of Justice in The Hague ruled on Thursday that Hungary and Slovakia had breached a 1977 treaty on harnessing the river Danube with dams at Gabcikovo, Slovakia, and Nagymaros, Hungary, to generate electricity. It ordered Hungary and Slovakia to negotiate in good faith to achieve the original objectives of the 1977 treaty and agree on a joint operational regime for the Slovak dam. "I hope both sides will be reasonable enough to reach an agreement, as asking for arbitration could protract the whole case maybe for years," Peter Tomka, a legal expert of the Slovak foreign ministry, told a news conference. He said the two sides could solve their mutual compensation claims by what he called a zero solution. "(If no compromise were found) the matter could become very complicated as Slovakia could also seek damages caused by transformation of the Gabcikovo electric power plant to one for continuous power production rather than the originally planned peak production," Tomka said. The court said each state was obliged to pay compensation but suggested the claims could be dropped under a broader deal. Tomka said Slovakia would name its delegation to the talks at the beginning of October. A Hungarian government spokesman said Budapest would also name a delegation soon. The two sides have six months to agree on how to implement the verdict and then either side may unilaterally return to the tribunal for arbitration on remaining points of contention. The plan to exploit the Danube for hydro-electric power, improve navigation on the Bratislava-Budapest sector of the river and protect the region against floods, started as a joint project and envisaged building twin dams, one in each country. Budapest stopped work on its dam in 1989 under pressure from environmental groups and in 1992 abandoned the project. But Czechoslovakia completed its part of the work which was taken over by Slovakia after Czechoslovakia split in 1993. Some analysts say talks may be clouded by cool relations between the two states, particularly over the treatment of Slovakia`s 500,000-strong Hungarian minority.