Europeans have also warned Iran: If there is no agreement by June-July, "a significant wave of sanctions will be imposed," a source told The Jerusalem Post.
"The US wants to link a new nuclear deal with Iran to oblige it not to support Middle East (resistance) groups, but this option will not work," he added.
This comes after an increase in tensions between the US and Iran.
The exercise includes drills on striking maritime targets, damage control, and joint search-and-rescue operations.
Iran has been a daily zig zag of messages, one day trumpeting negotiations with the West as possible, the next day saying its impossible, and the next day saying diplomacy is desirable again.
In a meeting with senior Iranian officials, Khamenei said the aim of Washington's offer for negotiations was to "impose their own expectations," Iranian state media reported.
Trump said on Friday that something will happen with Iran very soon, adding that he hopes it's a peace deal that blocks the rival from obtaining a nuclear weapon.
The report came amid suggestion that Russia had sent officials to Iran during the 15-month war between Hamas and Israel.
Even destroying the nuclear program will not change Iran’s fundamental goals expressed in its constitution, nor the threat it presents to humanity.
The stock of uranium refined to up to 60% in the form of uranium hexafluoride grew by 92.5 kg in the past quarter to 274.8 kg, one of two confidential IAEA reports said.