The year 2007 is the year of opening the critical mass of chapters of the EU acquis communautaire, while 2008 will be marked by their closure, Rehn said.
Speaking about the year 2009 as a possible target year, Rehn said that the pace of reforms was important for negotiations and membership.
It is useful for candidate countries to set target dates, and having a goal is good because it encourages reforms. But that goal is not binding for the European Union, Rehn said.
Croatia's progress depends solely on the implementation of reforms, the EU official said, adding that Croatia's progress in the accession process would not be affected by outstanding issues with Slovenia either.
He said that he expected Slovenia to focus on bringing Western Balkan countries closer to the EU during its presidency in the first half of 2008, as well as that this would be a priority for Portugal, which takes over EU presidency after Germany, and for France, which is to chair the EU in the second half of 2008.