An American think-tank is calling on Canada, the United States and Mexico to combine customs, immigration and security functions to the point

at which borders become almost irrelevant.

A study released yesterday by the Carnegie Endowment for International Peace urges the three countries to explore whether a North American 'integration project' is worth pursuing and to develop a strategic plan for rethinking border relationships.

A decision to proceed would trigger bilateral negotiations with the aim of agreeing on the border relationship each pair of neighbouring countries wishes to see in 10 or 15 years.

'For the U.S.-Canada border, this means ever closer and organic co- operation, an ever more explicit focus on understanding and addressing differences and ever greater experimentation,' says the study, prepared by the endowment's International Migration Policy Program.

'It is in fact our contention that, substantively at least, the U.S.-Canada border is likely to disappear before any politician finds the political courage to negotiate its removal.'

The study's authors, Demetrios Papademetriou and Deborah Waller Meyers, spent two years researching the issues, paying special attention to life in border communities.

The study acknowledges the sensitivities around fostering closer ties between sovereign countries and insists the proposals would not lead to the creation of a new political entity, nor a continental capital akin to Brussels in the European Community.

It also stresses that stronger border co-operation would not unduly affect areas the partners consider 'nearly sacred' - such as issues of identity and, in Canada's case, a tradition of government-sponsored social programs.

Canadian and U.S. leaders see more effective border management as a pressing issue, insisted Martha Nixon, a senior Immigration Department official who attended a Washington conference yesterday to discuss the report's findings.

'They have asked us to make this a much more strategically focused piece of business, so I think it's clear this is a priority.'

The authors say continental integration is based on a vision that imagines the NAFTA borders gradually 'becoming irrelevant to the point where their abolition could proceed without any real compromise' in any of the priorities of each partner.

Meyers said the rapid growth in commerce between the countries demands a forward- looking approach to ensure border systems can handle the flow of goods and people.

'Maybe things aren't collapsing yet, but they will if we don't do anything,' she said in an interview.

Among the authors' ideas

* One partner conduct all inspections and tariff collections on behalf of the other two countries when cargo enters NAFTA space, eliminating the need to repeat procedures at each border. A similar system could be implemented by immigration services to deal with people crossing borders.

* Canada and the United States, initially, agree to a common visa regime for the widest band of countries possible.

* Canada and the United States gradually liberalize the movement of each other's citizens, building on the treatment each now offers one another's professionals under the NAFTA agreement.

The authors believe the proposals could enhance protection against illegal activities such as terrorism and drug- smuggling, improve economic prosperity and insulate each country from 'political ups and downs' that affect vital interests. For instance, some U.S. politicians have been pushing for stricter border controls that would, in turn, hurt businesses.

The study says U.S. interest in the integration project is 'likely to be tepid' unless the proposals can help Washington accomplish its own goals less expensively, more efficiently and much more effectively.

Nixon, an assistant deputy minister with Canada's Immigration Department, does not believe the sort of changes outlined in the report would water down sovereignty or lead to erasure of the border.

'I think we can do a whole lot without sacrificing or challenging our identity at all.' She pointed to a pilot project that will allow people crossing the Bluewater Bridge at the Canada-U.S. border near Sarnia, Ont., to fill out forms at just one stop instead of two.

'Why do we have two places to go to?' she asked. 'Why don't we have one pass between two countries?'