Billed as a treaty of "reconciliation and friendship", the document aims to end decades of mutual animosity while at the same time boosting both countries' chances of joining Nato and the European Union.
Under the terms of the treaty, Budapest is to renounce any claim to Transylvania, the territory it ruled as part of the Austro-Hungarian empire up to the end of the First World War. Romania has agreed to guarantee a range of rights to its large ethnic Hungarian minority.
Western officials have joined the governments of both countries in hailing the move as a breakthrough and an important step towards enhancing stability in the region. "The treaty will benefit both nations as well as Europe," the Romanian President, Ion Iliescu, declared earlier this month. Robert Hunter, the United States ambassador to Nato, put it more bluntly: "It is now impossible for Hungary and Romania to go to war."
For all that, critics have denounced the treaty as a sham, a meaningless piece of paper which instead of genuinely seeking to settle old scores is designed simply to curry favour with Nato and the EU, institutions that both Budapest and Bucharest are desperate to join.
Romanian nationalists, who have long accused Budapest of harbouring territorial designs on Transylvania, have argued that it gives away too much. Hungarian nationalists, who still curse the 1920 Treaty of Trianon under which the country lost two-thirds of its territory, say it gives away too little. Meanwhile, members of Romania's 1.6 million-strong ethnic Hungarian minority - the very people whose rights the treaty is supposed to enshrine - have accused Budapest of a sell-out.
"It is clear that the treaty was signed under pressure from foreign countries," said Laszlo Tokes, the ethnic Hungarian priest who sparked the 1989 Timisoara protests and who is now a leading spokesman for the ethnic Hungarian cause in Romania. "But although it may look very good, it is totally lacking in substance."
After more than 70 years under Bucharest, ethnic Hungarians in Transylvania protested that they were victims of successive policies of assimilation, the end aim being the erosion of their Hungarian identity. Rather than ending with the downfall of Nicolae Ceausescu in 1989, moreover, they say the process has carried on unabated. For the ethnic Hungarians of Romania the only acceptable solution would have been extensive autonomy in the regions where they constitute a majority. But that was totally unacceptable to Bucharest.
In the treaty to be signed today, the issue has been fudged. Whereas it contains a host of regulations on minorities as laid out by bodies such as the United Nations and the Council of Europe, it also includes a footnote ruling out any form of collective rights or territorial autonomy along ethnic lines.
But for all its imperfections, others see it as a step in the right direction. "The treaty was a compromise and in a compromise you never end up with what you really want," said Gabor Szentivanyi, the Hungarian foreign ministry spokesman. "They may be limited, but after today ethnic Hungarians in Romania will have more rights that they do at the moment."
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