UPDATE It has been 2 hours. There is still mixed reporting. According to Reuters, Qatar said Iran had agreed to the ceasefire. The ceasefire has not been confirmed or denied by Iran or Israel. Iran and Israel are still both attacking. Trump’s post said that the ceasefire must begin within 6 hours, that would be midnight eastern time.
In my own personal judgement, I can not definitively say whether the ceasefire is real or fake.
https://www.reuters.com/world/middle-east/trump-announces-israel-iran-ceasefire-2025-06-23/
UPDATE 2 It has been 3 hours since Trump’s posts.
Fars News reports that “The ceasefire proposal put forward by U.S. President Donald Trump is completely false and was floated to distract public attention from the recent humiliation suffered by the United States following attacks on its bases in the region.” Fars News Agency is managed by the IRGC, therefore I consider it to be reliable on reporting decisions of the Iranian government.
https://xcancel.com/DropSiteNews/status/1937308597467132090#m
Iran Foreign Minister Seyed Abbas Araghchi says that there is no ceasefire agreement. “As of now, there is NO ‘agreement’ on any ceasefire or cessation of military operations. However, provided that the Israeli regime stops its illegal aggression against the Iranian people no later than 4 am Tehran time, we have no intention to continue our response afterwards.”
https://xcancel.com/DropSiteNews/status/1937313778451763487#m
It’s worth noting that a ceasefire can be a strategic weapon in a war of attrition, so long as you know it’s temporary and take the time to re-arm.
We have seen brief (basically unilateral decision by Russia) ceasefires between Russia and Ukraine where Russia takes the opportunity to re-arm/examine strategy and Ukraine just takes any respite they can get.
Iran accessing and potentially relocating weapons currently unusable due to the initial Israeli attack and limited regional air superiority (caved in storages where the actual weapons are fine just inaccessible currently for example) is much more valuable than Israel re-upping their air defense for it to just be depleted again.