David Doran, a businessman and neighbour of Dr Reilly, is claiming that the construction precludes his family's ability to enter the beach. The case is listed in the Dublin Circuit Court for tomorrow morning -- hours before the most devastating Budget in the history of the State is revealed in the Dail.
Dr Reilly is not expected to appear in the court, with lawyers from both parties set to discuss the disclosure of relevant documents.
It's understood that Mr Doran's lawyers will tell the court that the wall "unfairly blocks" the family's ability to access the beach.
His legal team will claim that his attempts to deal with the matter outside of court have failed.
Mr Doran is understood to have directly contacted the Health Minister over the matter but the pair failed to reach agreement.
Dr Reilly and Mr Doran's homes are right beside each other, looking out onto Rush beach at the rear.
A laneway that previously provided access to the beach was blocked when Dr Reilly ordered the construction of the fence, it will be claimed.
Mr Doran will allege that his "right of way" has been denied by the structure.
The seaside property is the family home of Dr Reilly, who also owns a country mansion in Co Offaly.
While the dispute is being played out in the circuit court, Dr Reilly will be in the Dail detailing €650m in health adjustments.
The news that he is now embroiled in a land dispute will prove particularly embarrassing for Dr Reilly whose affairs have been the subject of major controversy in recent weeks. In July, the Dublin North TD was listed as a debt defaulter for being one of four investors who failed to pay a €1.9m debt in relation to a nursing home.
And the Minister has faced a number of calls for his resignation over his handling of the Health service and the escalating HSE deficit.
The Department of Health said it would not be commenting on the matter.