Commercial airlines around the world on Monday were weighing how long to suspend Middle East flights as a conflict which has already cut off major flight routes entered a new phase after the U.S. attacked key Iranian nuclear sites and Tehran vowed to defend itself.

“If the Middle East is unstable, the world will not be at peace,” Chinese President Xi Jinping said Thursday. “If the conflict escalates further, not only will the conflicting parties suffer greater losses, but regional countries will also suffer greatly.”

The world's largest cryptocurrency gained alongside gold and oil futures indicating that traders anticipate a limited conflict rather than a prolonged geopolitical crisis.