Fighting broke out on Feb 28 when the United States, backed by Israel, attacked Iran, killing former supreme leader Ayatollah Ali Khamenei and several senior military commanders.
The attacks prompted Iran to launch retaliatory missile and drone strikes against Israel and US allies in the Gulf.
A ceasefire took effect on Apr 8 but diplomatic efforts to permanently end the war have yet to produce a settlement.
Among its conditions, Iran has also called for an end to hostilities on all fronts, including in Lebanon, where Tehran-backed Hezbollah fighters have been battling Israel.
Despite their ceasefire, tensions remain high between Tehran and Washington.
Rezaei warned that Iran would “drag the war” beyond the Gulf if the United States resumed hostilities, bringing “another dimension to the war”.
But he added that “the possibility of war is low”.