Iraq militant push shrinks scope for Saudi-Iran detente

DUBAI (Reuters) - This week's advance by Sunni insurgents in Iraq provides a powerful argument for why Iran and Saudi Arabia should bury their Cold War-style feud, but is nonetheless likely to set back detente between the Gulf's dominant Sunni and Shi'ite powers.

After decades of often overt Saudi-Iranian hostility that polarised the Middle East - and three years of proxy war in Syria - the Sunni monarchy and Shi'ite revolutionary state had gingerly begun in recent months to explore ways to reach out.