While it is still seen as credible, the country has witnessed an erosion of values, Potočnik, who was Slovenia's chief negotiator in EU accession talks, has told the STA.

Commenting on the drop in support for the EU among Slovenians from 90% in 2003 to less than 50% today, Potočnik said that Slovenians had simply voted in 2003 in favour of affirming Slovenia as a nation that belongs into the EU, in favour of democracy and prosperity.

It later became clear that "membership alone does not guarantee prosperity", the EU environment commissioner said ahead of 1 May, which will mark the 10th anniversary of Slovenian membership in the bloc.

"The reform drive subsided, the cheap money was used for buyouts instead of development, prosperity was patched up with loans, the response to the crisis was slow and superficial," Potočnik said.

The people are disappointed and one needs to add to that the European story and the financial crisis "which contributed to an image of Europe without solidarity and to a seeming deepening of the stereotypes we know from the time of the former country - a thrifty north and a wasteful south".

Since joining the EU as the best pupil in the class of candidates, Slovenia has witnessed and erosion of moral and ethical values and is suffering from political interference in the economy, envy and political battles in which the interest of the people are put on the back burner, the commissioner argues.

"There is a lot of misleading and populism. In short, we haven't proven yet that we are really worthy of our own country and capable of managing it responsibly."

Potočnik sees the need to define clear strategic goals, but fears that the maturity needed to reach consensus is not there.

Slovenia's image in the EU has suffered as a result of the crisis, but the country is still seen in EU institutions as having effective and credible people. While in the past Slovenia's image was possibly even better than the country would deserve, Potočnik fears that the opposite will be true for a while now.

Asked about how the temporary blocking of Croatia's EU accession influenced Slovenia's image, he said it was of a double nature, being negative at first and then very positive when a solution was found that could serve as an example on how to approach a number of similar issues still open in the Balkans.

Potočnik meanwhile hopes that the EU will preserve its enlargement drive, as for him enlargement "has always been and will be one of the key if not even the most successful EU policy".

"It contributes significantly to facing financial and economic challenges as well to preserving stability and peace in the region."

Commenting on the declining public trust in the EU, he agreed that trust was at its lowest point, while adding it was still greater than towards national institutions.

Potočnik argues that countries and institutions need to work together "instead of resorting to populism and to finding scapegoats".

He is still a supporter of constructive criticism, while arguing in response to attacks on the European Commission for allegedly living in a bubble remote from citizens "that at the same time one needs to be aware that an effective Commission is the best defender of our interests in the EU".

As regards his future plans, Potočnik reiterated that he would be ready to seriously consider serving a third term as commissioner "in case the government establishes that this would be in the interest of Slovenia".