Assuming you are in the loop about the fact there's a war ongoing, Iran has a fractured leadership right now (by design, so they are not vulnerable to decapatitation attacks), and the US is lead by one of the most finicky and unscrupulous individual to lead a world power since WW2.
That looks like Iran employing its primary piece of leverage to try to get what it wants. It's sort of like training a dog, it does something you don't like, you punish it with strait closure. It does what you want, you reward it with strait opening.
Iran doesn't really have a huge amount of wiggle room, there's only so many ways they can inflict pain on their opponents. This is one of them, so they're using it.
I will admit it does resemble the animated shenanigans of a certain wascally wabbit.
save