With oil prices diving, the battle for regional dominance between Saudi Arabia and Iran could kick into a higher gear in 2015.
Recent years have featured flashpoints over influence in Bahrain, Iraq, Syria and Yemen.
OPEC's decision to keep oil production steady has created huge financial headaches for Iran, leading to increased risks that this rivalry could get out of hand. The Iranians could get more help from Russia, which also needs higher oil prices.
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"The Saudis have decided to create a very painful situation for the Iranians and Russians over next six to eight months," said Michael Moran, managing director at consulting firm Control Risks.
