Barroso's hiring in 2016 by Goldman Sachs, after 10 years at the head of the European Commission, sparked a huge media firestorm

An EU watchdog called Thursday for reopening the ethics case against former European Commission chief Jose Manuel Barroso who was previously cleared of breaking bloc rules by taking a top job with Goldman Sachs.

European Ombudsman Emily O'Reilly made the recommendation after revelations that Barroso met with a vice-president of the current EU executive, Finland's Jyrki Katainen, in a hotel last year.

The executive European Commission should "refer the case of the former Commission president back for an opinion by the Ethics Committee," O'Reilly said.

"Putting the matter to the ethics committee once more would demonstrate that the Commission has taken very seriously public concern over this affair and the damage done to the image of the EU institutions," she said.

In a tweet, Barroso denied that he had lobbied the EU, echoing previous denials that the October 25 meeting with Katainen was only to catch up with an old friend. He wrote: "I have not and will not lobby EU officials."

Barroso's hiring in 2016 by the US investment bank, after 10 years at the head of the Commission from 2004 to 2014, sparked a huge media firestorm with then French president Francois Hollande saying it was "unacceptable".

After a probe, an EU ethics committee cleared Barroso, who had waited the compulsory 18 months, of breaching ethics rules but criticised his "judgement" for taking the Goldman job.

Barroso had insisted in a letter to the head of the European Commission Jean-Claude Juncker that "I have not been hired to lobby for Goldman Sachs and I do not intend to do so".

O'Reilly's office said the ethics panel's initial assessment reflected a pledge from Barroso that he would not lobby the Commission, but added "this has now been put in doubt by a meeting" with Katainen.

It said the meeting appeared to be for the "purposes of lobbying" as it was registered as one with Goldman Sachs, but the two participants described it later as a private and personal encounter.