WASHINGTON/ANKARA (Reuters) - President Donald Trump will announce on Tuesday whether he will withdraw from the Iran nuclear deal and a senior U.S. official said it was unclear if efforts by European allies to address Trump’s concerns would be enough to save the pact.

Trump has repeatedly threatened to withdraw from the deal, which eased economic sanctions on Iran in exchange for Tehran limiting its nuclear program, unless France, Germany and Britain - which also signed the agreement - fix what he has called its flaws.

The senior U.S. official said the European allies had moved significantly in Trump’s direction on what he sees as the defects - the failure to address Iran’s ballistic missile program, the terms under which international inspectors visit suspected Iranian sites, and “sunset” clauses under which some terms expire.

The official did not know, however, if the Europeans had done enough to convince Trump to remain in the deal.

“The big question in my mind is does he think the Europeans have moved far enough so that we can all be unified and announce a deal? That’s one option,” said the official. “Or (does he conclude) the Europeans have not moved far enough and we say they’ve got to move more?”

European diplomats said privately they expected Trump to effectively withdraw from the agreement, which was struck by six major powers - Britain, China, France, Germany, Russia and the United States - and Iran in July 2015.

“It’s pretty obvious to me that unless something changes in the next few days, I believe the president will not waive the sanctions,” one European diplomat said, adding he saw only a “very small” chance that Trump stays in the deal.

European leaders have warned that Trump’s withdrawal would strike a blow to the alliance between Western Europe and the United States, and undo years of negotiations that they say were successful in halting Iran’s nuclear ambitions.

Iran has ruled out renegotiating the accord and threatened to retaliate, although it has not said exactly how, if Washington pulls out.

Trump gave no indication of which way he was leaning on Monday, saying only in a Twitter post that he would announce his decision at 2 p.m. (1800 GMT) on Tuesday.

IRAN BACKLASH?

Under the deal, formally known as the Joint Comprehensive Plan of Action (JCPOA), the United States committed to easing a series of U.S. sanctions on Iran and it has done so under a string of “waivers” that effectively suspend them.

Under U.S. law, Trump has until Saturday to decide whether to reintroduce U.S. sanctions related to Iran’s central bank and Iranian oil exports.

The reimposition of sanctions would dissuade foreign companies from doing business with Iran because they could be subject to U.S. penalties.

Bringing back U.S. sanctions could also trigger a backlash by Iran, which could resume its nuclear arms program or punish U.S. allies in Syria, Iraq, Yemen and Lebanon, diplomats said.

On Monday, Iranian President Hassan Rouhani suggested Iran could remain in the accord even if the United States dropped out but that Tehran would fiercely resist U.S. pressure to limit its influence in the Middle East.

Rouhani said the Islamic Republic had been preparing for every possible scenario, including a deal without Washington - which would still include the other signatories that remain committed to it - or no deal at all.

FILE PHOTO: U.S. President Donald Trump gestures after speaking at a National Rifle Association (NRA) convention in Dallas, Texas, U.S. May 4, 2018. REUTERS/Lucas Jackson/File Photo

“We are prepared for all scenarios and no change will occur in our lives next week,” Rouhani said in a speech broadcast live on state TV.

“If we can get what we want from a deal without America, then Iran will continue to remain committed to the deal. What Iran wants is our interests to be guaranteed by its non-American signatories. ... In that case, getting rid of America’s mischievous presence will be fine for Iran.”

Trump’s Iran tweet helped oil prices break $70 a barrel to reach their highest level since late 2014.

ALLIES COMMITTED TO DEAL

Britain, France and Germany remain committed to the accord and, in an effort to address U.S. complaints, want to open talks on Iran’s ballistic missile program, its nuclear activities beyond 2025 - when pivotal provisions of the deal expire - and its role in the wars in Syria and Yemen.

British Foreign Secretary Boris Johnson, in Washington this week, said the deal’s weaknesses could be remedied.

“At this moment Britain is working alongside the Trump administration and our French and German allies to ensure that they are,” he said in a commentary in the New York Times.

Johnson met U.S. Secretary of State Mike Pompeo and Vice President Mike Pence on Monday.

Diplomats say Iran would rather the deal remain intact out of concern about a revival of domestic unrest over economic hardships that mounted over the years sanctions were in place.

Sanctions imposed on Iran in early 2012 by the United States and European Union over its nuclear program cut Iran’s crude exports from a peak of 2.5 million barrels per day before the sanctions to a little more than 1 million bpd.

But Iran re-emerged as a major oil exporter in January 2016 when international sanctions were suspended in return for curbs on Iran’s nuclear program.

Iran’s clerical rulers have repeatedly ruled out reducing its sway across the region, as the United States and its European allies may seek as part of any new deal.

Underlining Tehran’s growing regional clout, pro-Iranian group Hezbollah and its political allies won just over half the seats in Lebanon’s parliamentary election, unofficial results showed on Monday.