Yet Congress passed a law, which Obama signed, whose primary intent was to ensure that before any Iranian Agreement entered into force the US Congress had to approve it. Admittedly the law stacked the game in Obama's favor by instead of requiring a 2/3rds majority to approve the agreement it would require a 2/3rds majority to defeat the agreement so it's clear why Obama signed it.
However now Obama is violating the clear intent of the law by taking the agreement to the UN before the US Congress has had a chance to vote on it.
The "excuse" is that we need to process the agreement expeditiously. Interestingly that did not seem to be a criteria when the deadlines for achieving an agreement slipped for months and months.
The reality is that Obama honestly believes he's an emperor not a president. He feels justified in ignoring Congress because they're, in his mind, keeping him from doing what he wants. Obama has expressed envy at the dictator who rules China since that monster doesn't need to get Congressional approval.
Well it appears that Obama has found a way to end his envy.
From unilaterally disobeying Federal Court orders about his illegal immigration reforms, to not defending laws he doesn't like, to bullying reporters who ask inconvenient questions Obama is showing that he's just like the dictators in China; he too doesn't have to listen to anyone else when he makes the rules.