Boeing

(BA) - Get Report

shares slipped Monday after the plane maker and

AMR

(AMR)

agreed on a deal allowing the parent of American Airlines to defer 54 of 56 aircraft originally scheduled for delivery between 2006 and 2010.

The arrangement allows American to postpone $1.4 billion of capital spending previously planned for 2005 through 2007 and a total of $2.7 billion in capital spending through 2010, according to a statement from the companies.

AMR said the move "will substantially enhance our ability to restructure our finances," particularly at a time when sky-high jet fuel prices are taxing operating costs.

Boeing said it had already factored the agreement into its financial guidance.

Boeing shares were down 29 cents, or 0.5%, to $53.48, while AMR's shed 17 cents, or 1.9%, to $8.73.