All Leisure 'remains committed to its US customers,' a UK spokesman told Seatrade Insider, and the three brands will be sold through the general sales agent Discover the World.
The spokesman cited a change in strategy that led All Leisure to make 'the difficult decision' to close the Fort Lauderdale-based sales office.
He added: 'We have been working closely with our staff in the Florida office to support them during this challenging period.'
All Leisure has had the US sales office since 2005, when it acquired that operation along with the ship Discovery, which it previously chartered. All Leisure sold Discovery in October.
Currently Voyager (ex Alexander von Humboldt) sails for Voyages of Discovery, while the leased Minerva sails for Swan Hellenic. Hebridean operates Hebridean Princess and markets a limited number of European river cruises.
Tucker, who is leaving, has served as North America president since early 2013, overseeing interactions with travel agents, sales and marketing, accounting, reservations and inventory.
Previously he was vp field sales for Silversea Cruises.