grounds for war

But he is unlikely to try in the Aegean, since Turkey has said that such a move would be grounds for war.

At that point Trump changed "President Putin was extremely strong and powerful in his denial today and what he did is an incredible offer;" to "President Putin was extremely wrong and bad in his denial today and what he did is grounds for war."

Such a step, China has said, would be grounds for war.

Since closing Pakistan’s airspace would hinder America’s ability to defend its forces in Afghanistan, Olson, the former ambassador, said the U.S. might regard such action as a “casus belli,” or grounds for war.

Any foreign government installation not expressly accepted by a host government is a serious breach of law, and may constitute grounds for war.