Iran, has a thirst to quench. A thirst for making an atomic bomb, just like the U.S. But European countries and the U.S do not want Iran to make,or in this case succeed in making a bomb.
Why? Because Iran isn’t too “responsible” in handling a bomb. Instead of using it like the U.S is, more along the lines of using it as blackmail. Israel, is an ally of the U.S and if Iran does indeed make a bomb, it will most likely hold it upon Israel as blackmail. So in order to prevent this, the U.
S and the European countries had set up economic sanctions, that do not allow Iran to trade with any of the European or the U.S. And they were slowly increasing it. But after decades there has been a breakthrough, there has been a six-month treaty that the economic sanctions will be reduced and in return Iran will slowly stop their bomb-making development.