The chief executives of 14 defense companies urged Congress on Monday to pass a defense spending bill for fiscal 2011 instead of extending the current stopgap measure that keeps funding at 2010 levels.

The failure of lawmakers to pass a defense appropriations bill for fiscal 2011, which began on October 1, could have serious consequences, the CEOs of Lockheed Martin Corp , Boeing Co's defense business and a dozen other companies said in a letter to congressional leaders.

U.S. Defense Secretary Robert Gates warned last week that Congress was causing a crisis on my doorstep by failing to approve Pentagon spending, inaction that could lead to a funding shortfall and hurt the military.

Failure to address funding decisions for individual national security programs on a full-year basis will lead to program dislocations, funding interruptions, and adverse consequences on U.S. employment not only in the current fiscal year, but for many years to come, the industry executives said in their joint letter, noting the current continuing resolution limited production rates and banned new program starts.

Robert Stevens, chief executive of the largest U.S. defense contractor Lockheed, said the defense industry faced schedule delays, higher costs and other unnecessary risks unless lawmakers pass a fiscal 2011 defense appropriations bill.

Without appropriate full-year funding decisions on national security programs, we will face costly schedule delays and breaks in production that will increase overall program costs and interrupt the delivery of critical equipment to warfighters, Stevens said in a separate statement.

U.S. lawmakers have not passed the fiscal year 2011 defense appropriations bill and the Pentagon, like the rest of the federal government, is operating under a stopgap measure that keeps funding at 2010 levels. Congressional inaction would effectively force the Pentagon to operate with $23 billion less than Obama requested for the Pentagon in the 2011 fiscal year, which runs through the end of September.

It has also forced NASA to keep developing a rocket it has said it does not want and the National Oceanic and Atmospheric Administration to delay launching two new weather satellites.

(Reporting by Andrea Shalal-Esa; editing by Steve Orlofsky and Andre Grenon)