Hamas: Israel severing security ties with PA is 'declaration of war'

This morning, Israel announced that it was closing the District Coordinating Office (DCO) in Jericho and that it was severing its security ties with the Hamas-led 'Palestinian Authority.' Hamas is now saying that Israel's decision to do so is "a declaration of war" and of course "against international law." I'd be curious to hear how Hamas believes that 'the Zionist entity,' which it does not