The signing takes place Sunday afternoon in Stowe ahead of the meeting of political leaders from the New England states and the premiers of the five eastern Canadian provinces in Stowe on Monday.
The agreement and meeting are happening as a bitter trade dispute simmers between Washington and Ottawa.
Republican Gov. Phil Scott’s office says the declaration builds upon an earlier cooperative agreement and advances collaboration in commerce, energy, environmental protection, transportation and tourism. Scott and Premier Phillipe Couillard are expected to sign the declaration at the summit of the Stowe Mountain Resort ski area.