The issue here is related to the implementation of Pan-Canadian measures. If criteria are established according to which all Canadian companies and citizens are treated the same way, regardless of where they are in Canada, with regard to the implementation of regulations or specific agreements, the signing of equivalency agreements will not remove the federal minister's responsibility in this regard. However, if it is acknowledged that the provincial regime on a given matter is equivalent to the federal one, the probability that the agreement will be cast aside is rather low.
On May 15th, 2006. See this statement in context.