^ Actually both sides did this (Public Board)
They kept offering fake deals and fake ceasefires, running out the clock. It took 2-3 months for each proposed deal to realize Iran wasn't serious.
The US's actions and the other side's reaction parallel this exactly. Both sides were posturing, screwing around and running the clock out. Kushner and Witkoff as US diplomatic envoys while they were grifting for their own deals didn't exactly build trust.
