BRUSSELS, Dec. 18 (Xinhua) -- The European Commission on Thursday expressed regret over Slovenia's announcement that it will block the opening of several new chapters in Croatia's accession negotiations with the European Union (EU) because of border disputes between the two former Yugoslav republics.
"The commission has consistently maintained the view that the border issue is a bilateral issue that should not be brought to the table of the accession negotiations," said Crisztina Nagy, a commission spokeswoman.
"We encourage Slovenia and Croatia to solve the open border issue in the spirit of good neighborly relations," she said.
Slovenia and Croatia have not been able to completely draw their land and sea borders since their independence in 1991.
France, which holds the current EU presidency, is investing substantial efforts to solve this dispute and the European Commission supports France's efforts, Nagy said.
"The commission regrets that Slovenia cannot accept the solution proposed by the (EU) presidency," Nagy said. "As a result, we now have a considerable number of chapters that are technically finalized but cannot be processed by the accession conference."
Slovenian Prime Minister Borut Pahor said Wednesday in Ljubljana that his country will veto the opening of seven new chapters because of the border dispute.
"We are reserved about seven chapters because the Croatian government submitted to the European Commission documentation which prejudges the border," Pahor said after meeting with the leaders of all parliamentary parties.
He said that Slovenia has reservations about another four chapters for other reasons.
Slovenia would consent to the opening of one and closing of three policy chapters as Croatia and the EU hold the next round of accession conference in Brussels on Friday, he said.
Nagy said the EU's commitment to ultimately taking in all Western Balkan states as members has not changed. She asked Croatia to continue necessary reforms to meet benchmarks for opening and closing negotiating chapters. With the reforms done, "the boxes can be ticked very rapidly" even if there is delay is some areas, she said.
The EU and Croatia started accession negotiations in October 2005. It had been hoped that negotiations would conclude by 2009 and that the country could become the 28th EU member state by 2010.