The unidentified official told reporters on Saturday that Iranian negotiators effectively abandoned all past agreements and instead sought to make more demands from participants.
"What getting ready [for the Vienna talks] meant was to come with [a] proposal that walked back any of the compromises that Iran had floated ... pocket all of the compromises that others, the US in particular, had made and then asked for more", the official said during a phone briefing.
The official went on to relay to reporters that it's believed Iran's bid to accelerate its nuclear programme is part of a larger effort to be in a better position to negotiate a nuclear deal during a later round of talks.
"I think, at a minimum, they believe they could accumulate more enriched uranium ... use more grand centrifuges as leverage for a deal that they think they could extract more from us", the official said.
The unidentified official further underscored that the negotiating tactic would ultimately not succeed.
The US unilaterally withdrew from the 2015 nuclear deal under the Trump administration in 2018, at a time when former US President Donald Trump baselessly accused Iran of violating the terms of the agreement and then moved to reimplement previously lifted sanctions against the nation.
Although tensions remained uneasy between the US and Iran for the remainder of the Trump term, the ties did not entirely improve as US President Joe Biden came into office. In fact, negotiations between the two parties have not yet proven entirely effective as the latest round of talks was recently called off.
US Secretary of State Antony Blinken commented on Friday that Washington pulled out of the talks after determining that Tehran was not "serious" about the negotiations. Blinken did not offer any explanation as to how Iran was not meeting expectations.
Not all hope has been lost.
Saturday's revelations from the unidentified State Department official indicated that the Biden administration still sees an opportunity for the nuclear deal to be taken up again. When asked if it was time admit the deal was no longer possible, the official told reporters that "we have not reached that point".
It presently remains unclear when a next round of talks involving the US may be held.
The latest comments emerged just as Iranian air defences fired a missile as part of exercises over the town of Natanz, the location of most of Iran's nuclear installations. The operation was reportedly part of a test to examine a "rapid reaction force".