Speaking to reporters after talks with Hungarian President Laszlo Solyom in Novi Sad on Sunday, Tadic said that Serbia's territorial integrity must not be questioned at international forums, either implicitly or explicitly.

"The (UN) principles are not changeable. Serbia will not attend any international forum at which UN principles are not respected," he said.

The conference on Southeast Europe, to be held in Brdo Pri Kranju in Slovenia on March 20, is expected to be attended by leaders from all countries in the region. This would be the first meeting of those leaders after 18 years, but it could be jeopardised by a dispute between Belgrade and Pristina about Kosovo's participation.

The Serbian side insists that Kosovo representatives participate in the conference under the official name UN Mission of Kosovo/Kosovo, while top Kosovo officials insist on attending the event exclusively as representatives of an independent country.

Today's talks between Tadic and his Hungarian counterpart in Novi Sad were held at the end of Solyom's three-day visit to Serbia's northern province of Vojvodina.

Solyom visited Vojvodina at the invitation of the local Hungarian minority party the Alliance of the Vojvodina Hungarians, on the occasion of March 15, the Hungarian national holiday commemorating the 1848-49 revolution.

At the end of the visit, the Hungarian president said that Serbia's treatment of ethnic minorities was exemplary, underlining their cultural autonomy.

"We are happy about the fact that minorities in Serbia enjoy cultural autonomy and that here, unlike some other countries where ethnic Hungarians live, national legislation does not ban the use of the Hungarian language or the right to education in Hungarian," Solyom said.

Solyom visited the Vojvodina Hungarians also at the end of last year to give his support for the establishment of a separate voter register for the Hungarian minority, a project that was successfully completed.