A High Court decision has cast doubt over the proposed €64m sale to N1 Property Developments Ltd of the majority shareholding in the Northside shopping centre in Coolock, Dublin.

Mr Justice Frank Clarke yesterday upheld arguments by Treasury Holdings Ltd that the manner of the proposed sale by BNY Trust Company (Ireland) Ltd and Ark Life Assurance Company of their stake in the centre to N1 breached certain provisions of a co-ownership agreement relating to the shopping centre.

The ruling is likely to force BNY and Ark Life to begin the sale process again by first serving a "for sale" notice on Treasury and casts doubt over the sale to N1.

The judge will discuss with the parties next week what form of orders he will make after they have an opportunity to study his complex reserved judgment.

BNY and Ark had brought the proceedings against Treasury to clear the way for the sale of their majority shareholding in the shopping centre.

The case centred on the proper construction of clauses of the co-ownership agreement, relating to any proposed sale by parties of their interests in the centre. BNY and Ark had agreed to sell their interest to N1, but the sale was called into question by Treasury which alleged it would breach the co-ownership agreement. In their action, BNY and Ark asked for court orders directing Treasury to withdraw that claim.

BNY and Ark Life own 78.6 per cent of the shopping centre while Treasury is the beneficial owner of the remainder.

Yesterday, Mr Justice Clarke found that BNY and Ark, because they had entered into "put and call" options with N1 relating to the proposed €18.75m sale, were not therefore free to engage in an open sale and had not properly invoked clause 4 of the co-ownership agreement.