Economics called highest hurdle facing Irish unity

The financial cost of Irish unity is likely to be too great for a Dublin government to bear alone, and Britain is unlikely to supply long-term funding for a united Ireland.

These are the broad conclusions of eminent economist Sir Charles Carter, chairman of the Northern Ireland Economic Council, who spoke to top Dublin politicians at a public session of the New Ireland Forum.

The forum consists of members of the main parties in the Irish Republic and the mainly Roman Catholic Social Democratic and Labour Party from Northern Ireland. They are trying to hammer out a peaceful plan for Irish unity which would be attractive to the north's 1 million Protestants. But the pro-British unionists refuse to join such talks, and will not meet with a forum delegation visiting the north this week.

Distinct religious and cultural differences between the Catholic south and the Protestant north have been accentuated by a widening gap in living standards over the six decades of the Irish Republic's independence. The north receives $3 .4 billion in aid from Britain, and living standards are generally higher there than in the south. Figures given to the forum reveal that in health and social welfare alone, the north spends almost twice as much per capita as the south.

Professor Carter told the forum: ''I doubt if the Republic is in a position to make any proposition for simple reunification (that is) economically convincing or attractive.''

Prof. Louden Ryan of the Republic's national planning board underscored the grim economic reality in both parts of Ireland, where unemployment averages 20 percent.

Both economists presented cold, hard facts. But Charles Haughey, the Republic's opposition leader, gave his party supporters what they wanted to hear. Challenging the two speakers, he said: ''If economics is the dismal science, politics must be the profession of hope.'' He said he believed that an all-Ireland economy could be viable ''provided the economic structures are right.''

Haughey claimed that Britain would not refuse assistance to a new Ireland state, and that America and the Economic Community would provide ''parallel support,'' despite Professor Carter's reservations about such outside help.