"That election must be undertaken in a free, fair and transparent manner. It must also be free of taint and open to all Hondurans to exercise their democratic franchise," the State Department statement added.
Zelaya said Wednesday the coup d'état took place to oust him in preparation for "electoral fraud."
"I think [the United States] cannot put its prestige on the line and submit to a small group of people that are pro-coup and do not accept the opinion of the international community," Zelaya said Wednesday at a talk he gave at The George Washington University about democracy in Honduras.
"This is a first snatching of democracy during the Obama administration," he said.
Zelaya, who only had five months left of his term when he was ousted, said he would return to Honduras before his term ended in December – in one way or another.
In an interview with the Washington Post, Zelaya said that "When diplomatic action runs out, when the United States indicates it can't do any more, I am not going to simply sit around with my arms crossed."
He said he would look for "fighting strategies" and "seek actions on my return that kick the coup plotters out of power."
The Organization of American States suspended Honduras' membership, and the United Nations General Assembly unanimously condemned the coup. In the U.S., President Barack Obama denounced the coup and canceled $16.5 million in military aid to Honduras.
But despite international pressure and threats that Honduran elections will not be recognized by the international community including regional neighbors like Mexico, the interim government in Honduras has fastly held together.
"The degree of resistance of the de facto government has I think taken everyone by surprise -- their stubbornness," said McClintock, director of George Washington University's Latin American and Hemispheric Studies Program.
"The sanctions could backfire. We have to be careful about not being so across the board, and that we try to pass measures that hurt the de facto government," she said.
McClintock said that some of those measures like visa suspensions were articulated already by U.S. officials, but enforcement so far has been "sporadic."
"There's still US soldiers in Honduras. I think it's important to really stand very firm on the military aid and the withdrawal of U.S. military involvement with the Honduran military forces," she said.
"It's important to send signals to the Honduran military that it's not business as usual." Washington has had a difficult time choosing between a leftist Latin American leader who tried to pass a referendum that his opponents say could have lead to abolishing term limits, and a military ouster of a democratically elected President.
U.S. Rep. Ileana Ros-Lehtinen, R-Fla., ranking Republican on the House Foreign Affairs Committee, commented on the decision to pull aid from Honduras, "The U.S. approach to friends and foes is completely backwards. While appeasing the enemies of freedom worldwide, we punish those in Honduras struggling to preserve the rule of law, fundamental liberties, and democratic values."
Zelaya insisted that the real cause for the June coup was a power struggle by six of the most powerful families in Honduras, who he says control the economy and the national Congress. That is why, Zelaya said, the former President of the Congress is now the President of the Republic.
"He [Roberto Micheletti] named himself President," he said.