Northern Ireland's economy is being sold short through the failure to implement the Belfast Agreement, the SDLP's deputy leader has said.

Mr Seamus Mallon, who yesterday addressed a conference organised by Chamberlink, a joint venture between the Northern Ireland Chamber of Commerce and Industry and the Chambers of Commerce of Ireland, said that 18 months after the agreement, the institutional cross-Border arena "remains a void".

"I want to reaffirm today my abiding conviction that the agreement can be implemented, that the cross-Border void can and must be filled and that we can only achieve that transformation through dynamic partnership."

He did not believe the new devolved governments in Scotland and Wales would refrain from competing with the North for EU structural funds from 2000 to 2006. Every region was setting out its "own stall".

"Every day Northern Ireland delays establishing its new administration, every day we postpone, every day we procrastinate, every day we wait for someone else. The truth is that in doing so, we wave goodbye to another investment."

The North should be in the euro zone, he added. Harmonisation was Europe's watchword. "At the local level we already see the dislocation caused by the disparities in fuel costs," he said.

Mr Tom Clarke, president of the Chambers of Commerce of Ireland, said Northern Ireland's exclusion from the euro zone hampered trade between it and the Republic. Fluctuating exchange rates were a barrier to increased North-South trade. People in the North should have the power to decide on entry to the euro zone. A euro-sterling exchange rate mechanism option for mutual trade among Irish businesses should be explored, he said.

It was in the North's best interests to join the euro "if peace and cross-Border prosperity is our aim". "If I'm based in Dublin and have to choose to regularly import a product from Belfast or Brussels, the attraction of being guaranteed to know the cost of the Belgian product over a long period is obvious," he said.

Mr Owen Lamont, the NICCI president and managing director of NTL Ireland, said the Internet had banished peripherality. Business-to-business e-commerce was where the opportunities lay.