PANAMA CITY — U.S.-based Boeing has concluded an agreement with Panama's Copa Airlines for a $6.6 billion purchase of 61 airline jets on the sidelines of the Summit of the Americas.

The deal for the 737-MAX planes will be signed during a meeting between President Barack Obama and Panamanian President Carlos Varela, who is hosting this year's conclave of Western Hemishere nations.

Officials say the deal is the biggest between Panamanian and U.S. companies.

Copa says it will use the planes for its longer South American routes.

The 737 is the best-selling jet in the history of aviation. The MAX is a new version of it with more fuel efficient engines.