Leading article: Enlargement: the latest, but not the last enlargement

Bulgaria and Romania will be admitted as full members of the European Union in January, the European Commission announced yesterday. That the original timetable will be met reflects well on the EU and the two accession states. The Commission honoured its commitment to the latest enlargement, and Bulgaria and Romania worked hard to overcome known shortcomings in their judicial and economic systems. Once again, the promise of EU membership has been vindicated as an effective mechanism in raising standards of government and civil rights.

Announcing the decision, the Commission's President, Jose Manuel Barroso, stressed that the two countries would be closely monitored for compliance with EU regulations on corruption, food safety and that backsliding could precipitate suspension from the relevant EU provisions. This is the right way round: continued incentives to comply are likely to be more effective than a further extension of the waiting period for full membership that could feed doubt and cynicism among Bulgarians and Romanians about the EU's good faith.

The rejoicing in Sofia and Bucharest, however, was surely augmented by the sense that these two countries were getting into the EU just under the wire. The previous day, Mr Barroso had stated that there should be no further expansion until the EU had decided what to do about its aborted constitutional treaty. This raised question marks over the ambitions, first of Croatia, then of other republics of the former Yugoslavia, and then - of course - of Turkey.

One interpretation of Mr Barroso's remarks was that there would be a clear pause, if not a complete halt, in the EU's expansion. We hope, however, that a more positive gloss applies. So far, the lack of new institutional arrangements seems not to have impaired the EU's functioning a great deal - which is a tribute both to the strength of the central idea, and the desire of the current 25 members to make it work. But it is also true that there have been times when the EU could have been more effective - the recent conflict in Lebanon comes to mind - had it spoken with a single voice.

Rather than accepting that expansion must stall, the EU should take Mr Barroso's remarks as a challenge to restart discussion of institutional reform. This time, proposals should be stripped down to practical essentials, with a view to nothing more ambitious than efficient and equitable administration of the enlarged EU. Countries such as Germany, which is committed to Croatia's early accession, and Britain, which supports the general principle of enlargement, would have an interest in a swift and positive outcome. It is not only aspiring EU members who can benefit from incentives, but existing members too.