TEHRAN — Iran's armed forces were calibrating an attack on Israel after the death in Tehran this week of Hamas political leader Ismail Haniyeh, which has pushed the two enemies once again closer to the brink of a direct military confrontation. 

Immediately blaming Israel for the assassination, Tehran pledged revenge at a moment of heightened escalation in a region already on edge due to the repercussions of the Israeli war on Gaza. 

Yet even as Iran's civilian and military officials continue to express seriousness in their warnings, the fashion and the timing in which the promised attack is to be carried out remains unknown. 

Maj. Gen. Mohammad Bagheri, the chief of staff of the Armed Forces of the Islamic Republic, told the Tasnim News Agency on the sidelines of a state-organized Haniyeh funeral in Tehran on Thursday that the Islamic Republic was weighing its options and was in coordination with the "resistance front" in the region to decide how to respond to Israel. In Iranian political terminology, the "resistance front" refers to a network of Tehran-backed allied militia groups, including the Hezbollah in Lebanon, armed Palestinians groups, the Houthis in Yemen and a host of Shiite organizations in Iraq.