 Complete the following phrase:  Prior to Canadian Confederation, duty-free status had already been accorded by New Brunswick, Nova Scotia and Canada to one another, each contingent on the other colonies granting such status. There was also free trade between the colonies of British North America and the United States of America under the 1854 Reciprocity Treaty, but the United States had served notice in December 1864 that it wished to seek changes to the Treaty, including modifying the rights of transit of goods from Canada through the United States. As goods from Canada were previously allowed to pass through the US in bond to ports in New Brunswick and Nova Scotia for transshipment to Britain, this represented a potentially significant non-tariff barrier that was on the minds of participants during the 18651867 intercolonial conferences that took place in Charlottetown, Quebec and 