US calls for Iran's immediate release of detained US citizens

The United States called on Iran Sunday to immediately release US citizens and other foreigners detained on "fabricated" national security charges, after Tehran said an unnamed American has been sentenced to 10 years in prison.

"We call for the immediate release of all US citizens unjustly detained in Iran so they can return to their families," a State Department official said.

The statement made no specific reference to any individual, but it came after an Iranian spokesman announced the sentencing of an unidentified US citizen for alleged "infiltration" of the country.

"The Iranian regime continues to detain US citizens and other foreigners on fabricated national security-related charges," the official said.

"The safety and security of US citizens remains a top priority. All US citizens, especially dual nationals considering travel to Iran, should carefully read our latest travel warning."

Washington and Tehran have had no diplomatic relations since April 1980 in the wake of the Islamic revolution, and tensions have sharpened under US President Donald Trump after a brief warming under his predecessor, Barack Obama.

The two countries along with the other great powers signed an accord July 14, 2015 aimed at curbing Iran's nuclear program. Washington has continued to honor the accord despite Trump's threats as a candidate last year to "rip it up."