Asked about different interpretations of the Commission's decision to allow Croatian wine producers to use the name of Teran even though Slovenia had secured protected designation of origin (PDO) status for it, Hogan said there "may be a misunderstanding over the use of the Teran name referring only to a grape variety".

"Croatia never asked permission to call its wine Teran and the Commission would have never authorised it," he said, explaining the wine named Hrvatska Istra uses a grape variety that "happens to have the same name".

Allowing this, under strict conditions and only for that purpose, is perfectly within EU rules, he said, repeating there were numerous other examples from the wine sector in the EU of just this kind of exception.

Hogan rejected Slovenia's fear that Slovenian producers of Teran will suffer economic damage and that the Teran grapevine area in Croatia can be extended from what Slovenia says are 2,400 ha of land and not 300 ha as claimed by the Commission.

"There will be no economic damage to Slovenian producers because of this derogation - in fact it will contribute to strengthening the market position of Slovenian Teran producers."

"The derogation clarifies the exact labelling specifications that the Croatian producers of Hrvatska Istra need to apply, and so will prevent abuses...There are only around 300 ha planted with Teran grapes within the Hrvatska Istra vineyard, and this is the only Croatian wine allowed to use the grape name," he argued, saying the area was strictly defined.

The commissioner also rejected Slovenia's claim the Commission had not acted in good faith and transparently, as it did not try to solve the problem during the accession negotiations where the unanimity is needed, knowing that Slovenia would oppose the derogation.

"We always encouraged and gave Slovenia and Croatia time to find a compromise solution acceptable to everyone. But, at the end of the day, if an acceptable compromise cannot be found at the political level even after two years of discussion, the letter of the law has to be followed, as it is in every other case, at the very least to put an end to the legal uncertainty."

As regards the European Ombudsman's view that the Commissions' refusal to disclose the documents requested by the Slovenian side constitutes maladministration, Hogan said that "even when it comes to transparency there are rules to be followed".

"I'm sure that the Commission services always acted in good faith when addressing the access to documents," he added, announcing a response by the Commission but refusing to comment in detail on what is an ongoing process.

While the Commission insists that using a delegated act is fine in such cases, Hogan acknowledged this was the first time it is acting on the basis of the CMO Regulation's Article 100 (3).

He argued this was the case because this regulation of the Common Market Organisation has only been in force since 2015, while adding that "similar provisions existed in the previous wine legislation and were used to update lists in similar circumstances".

As regards views in Slovenia that what has happened is an abuse of power against the interests of a small member state, Hogan said that "in the end of the day the Commission has to be fair and just to both Slovenia and Croatia".

"Both countries enjoy equal rights under EU law and will always be treated in the same way as a result, and I believe that the outcome we're looking at ensures just that," he said.

Hogan is looking forward to Tuesday's meeting with Slovenian wine producers "to discuss with them the background to and reasons for the approach that the European Commission has had to take".

Commenting on Slovenia's readiness to also bring the Teran issue before the EU Court, he said that access to the court was available to all member states "and it is a matter for Slovenia to decide if they wish to take this option".

"In such a case, the Commission will, of course, defend its stance," added Hogan, who spoke of Teran as a wonderful wine that Slovenian representatives were kind enough to present him with during the past two years when a solution to this issue was being sought.