The appointment of Pat Cox as an unpaid advisor to a former European Commissioner breached Commission rules and has been criticised by European Ombudsman P Nikiforos Diamandouros.

In a judgment issued today, the Ombudsman said he could not investigate a claim of possible conflict of interests against Mr Cox because the Commission had failed to follow its own rules.

From 2007 to 2010, Mr Cox acted as an unpaid special advisor to Meglena Kuneva, who was at the time the European Commissioner for Health and Consumer Policy.

In February of last year, the NGO Corporate Europe Observatory appealed to the European Ombudsman claiming that the Commission had failed to adequately address possible conflict of interest between Mr Cox's role as a special advisor and his paid activities for multinational businesses and lobbying firms.

The Commission had ruled there was no conflict as Mr Cox only advised Ms Kuneva on political communication relating to consumer affairs and not on policies.

However, today the Ombudsman announced that he decided the Commission failed to follow its own rules and it was therefore impossible for him to examine the issue of possible conflicts of interest.

Mr Diamandouros criticised the Commission and called on it to improve its rules for handling such cases.

Mr Cox is a former President of the European Parliament and former Fine Gael presidential hopeful.