U.S. stock futures point to a lower open after Moody's stripped the U.S. of its top credit rating. Moodys cut its credit rating on Friday a notch to Aa1 from Aaa due to likely difficulty financng the federal government’s growing budget deficit and the ramifications of rolling over existing U.

Moody's Ratings downgraded the U.S. credit rating by one notch, from a pristine Aaa to Aa1, citing persistent and rising government debt as causing the move.