The United States is considering establishing a new network of American military bases in Iraq to aid in the fight against the Islamic State, senior military and administration officials said Thursday, potentially deepening American involvement in the country amid setbacks for Iraqi forces on the battlefield.

Speaking to reporters aboard his plane during a trip to Italy, the chairman of the Joint Chiefs of staff, Gen. Martin E. Dempsey, described a possible future campaign entailing the establishment of what he called “lily pads” — American military bases around the country from which trainers would work with Iraqi security forces and local tribesmen in the fight against the Islamic State.

General Dempsey’s framework was confirmed by senior Obama administration officials, and comes after an earlier decision this week to send 450 trainers to establish a new military base to help Iraqi forces retake the city of Ramadi, the capital of Anbar Province. The general said that base could be the model for a new network of American training bases in other parts of the country.