The Vatican says it is still unclear if its representatives would meet Yugoslav President Slobodan Milosevic. Also other practicalities of the trip are still being worked out, as any flight to Yugoslavia would need the backing of Nato.

Vatican sources also said the delegation to the predominantly Serbian Orthodox country would probably be a high-level one, possibly led by the Vatican Foreign Minister Archbishop Jean-Louis Tauran. More details were expected later on Wednesday.

Pope John Paul II has made several public appeals to the combatants in the Kosovo conflict to return to the bargaining table.

News of the delegation came shortly after Vatican Secretary of State, Cardinal Angelo Sodano, held talks with a group of Russian politicians, including former Prime Minister Yegor Gaidar, who met President Milosevic earlier this week.

Church officials say the Pope wants to see an end to fighting and the re-opening of diplomatic channels.

The BBC Rome Correspondent, David Willey, says the Pope is extremely concerned about the effects of Nato bombing, and believes his views are shared by public opinion in many Nato countries.

Religious leaders join call

Other religious leaders have been lining up to join the call for a halt to the Nato air strikes.

The Archbishop of Canterbury, leader of the Church of England, has called for a return to the negotiating table.

The World Council of Churches, with over 300 member churches, has published a letter to UN Secretary-General Kofi Annan. It expressed profound concern over the Nato military intervention and called for an immediate moratorium.

Religious and historical complexity

The Pope, who is himself a Slav, is conscious of the religious and historical causes of conflict in the Balkans.

Religious leaders from across the Orthodox world have called for a halt to the Nato air strikes, condemning the action against their fellow Serbian Orthodox.

The Greek Orthodox Church condemned the action against "a heroic and Christian people such as the Serbs".

The BBC Religious Affairs correspondent Jane Little said such rhetoric reflects the depth of solidarity in the Orthodox world for the predominantly Orthodox Serbs, and highlights the complex religious and ethnic factors which make this conflict so explosive.

Kosovo is seen as the spiritual heartland of Serbian nationalism - symbolised by the hundreds of ancient monasteries and churches dotted throughout the region.

Ethnic Albanians in Kosovo are largely Muslim and the religious differences in the region are something local religious leaders have been trying hard to keep out of the conflict.