* Infection kills more than 1,400 in Iran
* Worst-hit country in the Middle East
* Nowruz is most important date in Iranians' calendar
* Many go to Caspian coast, defying advice to stay home (Adds Rouhani's message to Americans)
By Parisa Hafezi
DUBAI, March 20 (Reuters) - Iran's Supreme Leader Ayatollah Ali Khamenei, in a speech on state television for the Persian New Year, praised Iranians for their "dazzling" sacrifices in fighting the coronavirus outbreak in the worst-hit country in the Middle East.
Khamenei, Iran's highest authority, said it had been a tough year for Iranians who have endured U.S. sanctions, floods, and the coronavirus, which has killed more than 1,400 people in Iran and infected nearly 20,000.
"These acts of sacrifice were made by medical groups, physicians, nurses, assistants, managers and the staff working in hospitals," said Khamenei, who looked healthy despite rumours he had been infected with the new coronavirus.
Officials close to Khamenei have denied the rumours.
Nowruz, or "new day" in Persian, is an ancient celebration and the most important date in the calendar, when families gather and exchange gifts. But the coronavirus has overshadowed celebrations.
"Last year was a tumultuous year for the Iranian nation," Khamenei said. "It was a year that began with the floods and that ended with the coronavirus ... but we will overcome all hardships with unity."
He named the new year "The year of boosting production."
In a separate message, President Hassan Rouhani said Iranians praised doctors and nurses for their courage in fighting the disease.
Millions of Iranians are now confined within their own walls for the New Year celebrations. But police said many defied warnings by health officials to stay home and avoid crowds by heading to the Caspian coast, a favourite destination during the Nowruz holidays.
The United States sent Iran a blunt message this week: the spread of the coronavirus will not save it from U.S. sanctions that are choking off its oil revenues and isolating its economy.
Rouhani urged Americans to call on their government to lift sanctions as Iran fights the coronavirus.
"U.S. government sanctions have led to many ordinary Iranians losing their health, jobs and income," he said.
"Now is the time for the American people to shout loudly at the U.S. government to demand an answer ... and not allow the U.S. history to be blackened further."
Foreign Minister Mohammad Javad Zarif said on Twitter: "(The) U.S. administration gleefully takes pride in killing Iranians citizens on #Nowruz... The White House takes its 'maximum pressure' to a new level of inhumanity with its utter contempt for human life."
"A UNIQUE SPEECH"
Unlike his usual fiery speeches, Khamenei refrained from attacking Iran's longtime foe in his remarks.
"Iran benefited from America's sanctions. It made us self-sufficient in all areas," he said.
Friction between Tehran and Washington has increased since 2018 when U.S. President Donald Trump pulled the United States out of Tehran's 2015 nuclear deal with six nations and re-imposed sanctions on the country, crippling its economy.
Iran on Thursday granted a medical furlough to imprisoned U.S. Navy veteran Michael White, who has been in prison since his arrest in 2018. His release is conditioned on him staying in Iran, U.S. Secretary of state Mike Pompeo said.
White was sentenced to at least 10 years in prison on charges of insulting Khamenei and posting anti-establishment remarks on social media under a pseudonym.
It is not clear exactly how many Americans Iran may hold, but Washington has warned Tehran that it would hold the clerical rulers directly responsible for any American deaths since the outbreak has infected the Islamic Republic.
But growing discontent over economic hardship, combined with the coronavirus outbreak's impact, could force Iran to choose diplomacy over confrontation with the United States.
"It was a very unique speech by the leader. His language was different, his tone was different and it was not hostile towards America," said an official in Tehran, who asked not to be named.
When asked whether Tehran and Washington might try to ease tensions, he said: "Americans know what they should do. First sanctions or at least some sanctions must be lifted. Then we will see." (Reporting by Parisa Hafezi and Dubai newsroom; Editing by Angus MacSwan, William Maclean and Pritha Sarkar)
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