His representative told the Irish Examiner that Mr Crowley, absent from the parliament due to illness, would hold a press conference and “deal with all issues” when discharged from care.

The build-up to the next European elections, in May next year, is already underway with speculation around who might run.

The longest-serving Irish MEP in Europe, the Bandon native has not been seen in Europe or attended any parliament committees or contributed to any votes since his re-election in 2014.

Mr Crowley, who uses a wheelchair due to an accident when he was a teenager, has been in and out of hospital for some time after operations and has been unwell.

He has made no public contributions in the EU parliament in over four years.

However, he is still entitled, like other MEPs, to claim a monthly salary of €8,484.05, as well as a €4,342 monthly expenditure allowance to cover office rent and constituency activities.

It is unclear if any staff still work for him in Brussels or Strasbourg, but staff are still at his office in Maryborough, Douglas. The phone numbers for the European contact points have been removed from his website.

According to VoteWatch Europe, a think-tank which tracks parliament votes and actions, Mr Crowley’s voting record ranks 751st out of the 751 MEPs.

The MEP left the Fianna Fáil parliamentary party when the party joined ALDE (Alliance of Liberals and Democrats for Europe) in the European Parliament.

A poll-topper in four consecutive European elections, he has not spoken in Europe since 2014.

Kieran Hartley, the substitute MEP for Mr Crowley, previously appealed to Fianna Fáil leader Micheál Martin to intervene.

Kieran Hartley

Speaking to the Irish Examiner, Mr Hartley reiterated his call for Mr Crowley to stand aside or to clarify his position.

Brian Crowley is a public representative nobody has been able to talk to for four and a half years,” said Mr Hartley. “Does he think it is right when he has not turned up and voted and Ireland is in such a difficult position with the imminent Brexit?

“How come we have been left with a democratic deficit? That was the reason the substitutes list is there. Is it right to accept full pay and not to be there to do his job? He has left nobody in the European Parliament. MEPs have had to cover for him.”

A local representative for Mr Crowley responded to queries, saying he is still out on sick leave.

“Once he gets discharged from doctors’ care, which he hopes will be soon, he will hold a press conference and deal with all issues,” said the representative.

There is speculation that some senior Fianna Fáil figures may consider running for the European elections next year, with names such as Cork North Central’s Billy Kelleher and Clare’s Timmy Dooley being mentioned among the party.

Fianna Fáil sources maintain no decision is likely to be taken until it is known if Ireland will see its number of MEP seats rise.