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ABOARD AIR FORCE ONE, Feb 19 (Reuters) - The United Statesplans to take no additional actions in response to pressure fromIran before talks with Tehran and major powers about returningto the 2015 Iran nuclear deal, the White House said on Friday.

Tehran and Washington have been at odds over who should makethe first step to revive the accord. Iran says the United Statesmust first lift former President Donald Trump’s sanctions whileWashington says Tehran must first return to compliance with thedeal.

The United States said on Thursday it was ready to talk toIran about both nations returning to the deal that aimed toprevent Tehran from acquiring nuclear weapons, which Trump, aRepublican, abandoned nearly three years ago.

U.S. acting Ambassador Richard Mills told the United NationsSecurity Council on Thursday that the United States wasrescinding a Trump administration assertion that all U.N.sanctions had been reimposed on Iran in September.

Iran reacted coolly, with Foreign Minister Javad Zarifsaying Tehran will “immediately reverse” actions in its nuclearprogram once U.S. sanctions are lifted.But White House spokeswoman Jen Psaki, speaking to reporterson Air Force One as Democratic President Joe Biden flew toMichigan, said "there is no plan to take additional steps" onIran in advance of having a "diplomatic conversation."

Under the deal, Iran accepted curbs to its nuclear programin return for the lifting of international sanctions. Washingtonreimposed sanctions after Trump quit the deal, and Iranresponded by violating some of the deal's nuclear limits.

Asked if the Biden administration was considering anexecutive order about reviving the agreement, Psaki noted theEuropean Union has floated the idea of a conversation among Iranand the six major powers that struck the agreement: Britain,China, France, Germany, Russia and the United States.

"The Europeans have invited us and ... it is simply aninvitation to have a conversation, a diplomatic conversation. Wedon’t need additional administrative steps to participate inthat conversation," she said.

The European Union is working on organizing an informalmeeting with all participants of the Iran deal and the UnitedStates, a senior EU official said on Friday.(Reporting by Alexandra Alper and Steve HollandEditing by Leslie Adler)