Health and Energy Minister Konrad Mizzi has lost a second senior aide in the space of 18 months amid reports of “serious divergences” between the two, the Times of Malta is informed.

Rennie Mercieca, who served in the minister’s private secretariat until a few days ago, would not comment when asked about his resignation and the “divergences” report.

“I don’t wish to comment about this and you should address your questions to the minister,” Mr Mercieca, from Paola, Dr Mizzi’s constituency, said curtly.

The ministry denied there were any arguments between Dr Mizzi and Mr Mercieca but confirmed the aide had stepped down.

The ministry denied there were any arguments but confirmed the aide had stepped down

Mr Mercieca was employed last year after the chief of staff, Joseph Montebello, resigned in May following an alleged row with the minister. Dr Mizzi denied firing Mr Montebello, who, a few weeks later, was appointed CEO of the Mediterranean Offshore Bunkering Company, which falls under Dr Mizzi.

The ministry said Mr Mercieca was not acting chief of staff, as it had been thought, but served as an adviser on industrial and labour relations. As an adviser engaged on a person-of-trust basis, Mr Mercieca was entitled to receive a different remuneration to that applicable to a chief of staff. The small unit, which deals with all the collective agreements signed by the government, is normally manned by civil servants. This newspaper is informed that Mr Mercieca’s posting at the bargaining unit was approved by the Principal Permanent Secretary, Mario Cutajar.

Asked on what basis Mr Cutajar had authorised the posting, a spokeswoman would only say that Mr Mercieca was moved to the bargaining unit.

“Since March 2013, there had been no other secondment to the bargaining unit before that of Mr Mercieca,” she added.

The spokeswoman declined to give details on Mr Mercieca’s remuneration.