An alliance of defense contractor associations and military advocacy groups is calling for Congress to agree to a fiscal year 2017 budget deal before the end of the calendar year.

The alliance, known as the Defense Related Associations, sent a letter Nov. 1 to House and Senate majority and minority leadership urging them to ignore the temptation to pass a stop-gap spending measure, or continuing resolution, that would continue into next year. The letter was released by the National Defense Industrial Association.

"There is always a temptation to extend the time for difficult final decisions. There will be plenty of those early in calendar 2017," the letter states. "However, a Continuing Resolution for defense that extends beyond the one under which we are currently operating will unnecessarily delay new programs, prevent the ramping up of mature programs, and affect defense readiness and operational issues."

The group is urging Congress to final FY-17 defense spending at "no less than the current Budget Control Act levels before the end of the calendar year in both authorization and appropriations acts."

Additionally, the group asks that Congress consider the "unpredictable national security challenges" facing the United States.

"If anything, the national security challenges that we face today are more daunting and complicated than they were eight months ago," the letter states. "Russian activities in the Crimea have been followed up with cyber adventurism that may end up affecting our 2016 elections. Syria and Afghanistan may be even more troublesome than was envisioned as the year began. Iran and North Korea are actively probing for weakness in US leadership and military posture."

Along with NDIA, some of the letter's signatories include the Aerospace Industries Association, the Association of the United States Army, the Navy League, the Air Force Association and the American Society of Military Comptrollers.