President Obama interrupted his vacation Thursday to announce that the United States will cancel a planned joint military exercise with Egypt to protest the government crackdown on Muslim Brotherhood protesters yesterday that killed over 500 people. But, Obama said, broader American interests mitigated against canceling the over billion dollars in US aid to Egypt at this time.

"Given the depths of our partnership with Egypt, our national security interests in this pivotal part of the world, and our belief that engagement can support a transition back to a democratically- elected civilian government, we’ve sustained our commitment to Egypt and its people," Obama said in a statement from Martha's Vineyard, Massachusetts Thursday.

"Our traditional cooperation cannot continue as usual when civilians are being killed in the streets and rights are being rolled back," Obama continued, saying the US had notified the Egyptian government earlier Thursday that it was cancelling the military exercise, Bright Star, planned for next month. "The Egyptian people deserve better than what we’ve seen over the last several days. The cycle of violence and escalation needs to stop."

US Defense Secretary Chuck Hagel, in a phone call with Egypt's defense minister and de facto military ruler Gen. Al-Sisi, "made it clear that the violence and inadequate steps towards reconciliation are putting important elements of our longstanding defense cooperation at risk," he said in a statement Thursday.