(Adds Khamenei's quote, detail)
By Parisa Hafezi
DUBAI, Feb 18 (Reuters) - Iran's Supreme Leader Ayatollah Ali Khamenei on Monday warned his country's government not to be deceived by European countries that say they want to salvage the 2015 nuclear deal abandoned by U.S. President Donald Trump last year.
The comments by the long-serving hardline cleric demonstrate the difficulty the elected government of pragmatist President Hassan Rouhani has in maintaining his policy of keeping Iran open to the outside world in the face of new U.S. sanctions.
Washington's major European allies have said they want to save the agreement under which world powers agreed to lift sanctions on Iran in return for curbs to its nuclear programme.
The Europeans have promised to guarantee that Iran benefits from abiding by the deal, even though Trump reimposed sanctions. In practice, European companies largely abandoned plans to reinvest in Iran after Trump's decision.
"America's enmity towards Iran is obvious," Khamenei said, according to state TV. "Europeans also practice deception today.... The enemy sometimes shows his teeth, sometimes his fists, and sometimes his smile. All these tactics are the same. Even their smile is out of animosity."
Since Washington walked out of the deal, Iran has so far continued to observe it. However, with few economic benefits to show for it, Rouhani has faced a backlash from conservatives.
The Trump administration says the nuclear deal did not do enough to curb Iranian meddling in regional affairs or restrict its missile programme. European countries say they share U.S. concerns about Iran, but that scrapping the deal would strengthen the hands of hardliners and undermine reform.
Britain, France and Germany are co-signatories of the deal along with Russia and China.
A new EU mechanism has been put in place to facilitate trade with Iran without using U.S. dollars, drawing a sharp rebuke from Washington. In practice, EU diplomats say it is likely to be used only for trade permitted by Washington anyway, such as for food or humanitarian supplies.
Iran has called on the EU to do more to demonstrate its commitment to the deal.
Khamenei, a hardline cleric in power since 1989, is Iran's ultimate authority, but the country is run on a day-to-day basis by the government of Rouhani, who won landslide elections in 2013 and 2017 on promises of opening Iran to the world.
"I am not telling the officials what to do, but I am advising them to exercise caution (in dealing with Europe), so that they will not be tricked by them and cause problems for the country,” Khamenei said.