American Airlines and JetBlue Airways are pushing ahead with an expansion of their partnership in the Northeast, even as a federal judge considers the government’s attempt to kill the deal.

The airlines said Friday that Fort Worth, Texas-based American will add six new routes from New York City while dropping one. New York-based JetBlue will start several new routes from New York and Boston including service to the Bahamas and Bermuda. Some routes will operate only during summer, and most will be limited to one or two flights a day.