On Thursday, international mediators and Tehran reached a preliminary nuclear deal, with Iran agreeing to stop stockpiling material that could be used to build an atomic bomb and to give international monitors greater access to its nuclear facilities.
"I think the alternatives are not either this bad deal or war. I think there is a third alternative, and that is standing firm, ratcheting up the pressure until you get a better deal… It's achievable," Netanyahu said.
On Friday, Netanyahu said the country's ministers unanimously opposed the Thursday framework deal between P5+1 countries, comprising Russia, China, the United States, the United Kingdom, France and Germany, and Iran.
Tehran and the P5+1 group have agreed with Iran on a number of key issues that include uranium enrichment, the number of centrifuges and sanctions imposed on the Islamic republic.
A comprehensive deal on Iran's nuclear program is expected by the end of June.