Islamabad, Sep 27 (ANI): Pakistan would treat it as "an act of war" if India revoked the Indus Water Treaty regulating river flows between the two nations, Pakistan's top foreign ministry official said on Tuesday, amid escalating tensions between the nuclear-armed neighbours. India has been seeking ways to punish Islamabad after 18 soldiers in the Kashmir region were killed in an attack. India on Tuesday said it summoned the Pakistani High Commissioner in New Delhi and informed him about the arrest of two men it alleges helped the gunmen illegally cross the disputed border before their attack.