The move came four days after the US-Israeli air war on Iran began, prompting heavy criticism from US lawmakers that the State Department was late in warning Americans to leave the region and that this showed poor planning and "incompetence".
"The Department is facilitating charter flights from the United Arab Emirates, Saudi Arabia, and Jordan for American citizens, and will continue to secure additional capacity as security conditions allow," the Department said in a statement.
Assistant Secretary for Global Public Affairs Dylan Johnson also said the Department was "actively securing military aircraft" for Americans who wished to leave the Middle East but did not elaborate.
Speaking to reporters on Capitol Hill, US Secretary of State Marco Rubio said there were about 1500 US citizens who requested assistance with departure and that the department was working to identify charter flights and military flight options while speaking with airlines to send bigger airplanes with more seats.
On Monday, the Department urged Americans across 14 countries in the Middle East to immediately depart the region using "available commercial transportation" without offering any US-government-vouched means.
The US Embassy in Jerusalem in a statement said it was unable to offer assistance to Americans trying to leave, although an official later said assistance was being offered.
The scramble has triggered accusations and criticism from US lawmakers.
Senator Brian Schatz of Hawaii, the top Democrat on the subcommittee that oversees State Department spending, told Reuters: "President Trump said the biggest surprise is that Iran retaliated against our assets and partners, but that expected retaliation was the administration's stated reason for our attack. The result is that Americans are stuck and in danger."
Speaking to reporters in the Oval Office earlier on Tuesday, President Donald Trump asked why there were no plans to evacuate US citizens.
"It all happened very quickly," referring to the war with Iran.
Former Republican congresswoman Marjorie Taylor Greene, who resigned from Congress after a split with Trump, said in a social media post: "The betrayal is unbelievable".
"American tax payers are forced to give Israel $3.8 BILLION every single year, and here is our own US embassy in Jerusalem telling Americans good luck getting out, you are on your own."
US security alerts for Americans in Kuwait, the United Arab Emirates, Iraq, Qatar and Bahrain, which urged them either to shelter in place or be prepared to do so, were disseminated after the US-Israeli joint strikes on Iran began, according to time stamps on social media posts by the US embassies in those countries.
