Security officials are monitoring increasingly worrisome signs as President Trump considers another military campaign against Iran.

"There are capabilities Iran did not fully employ in the previous round," a former senior Israeli military analyst told Newsweek.

Iran agreed a secret 500 million euro ($589 million) arms deal with Russia to acquire thousands of advanced shoulder-fired missiles, the Financial Times reported on Sunday.

President Trump is pressuring Iran to either curtail its nuclear program or face military strikes, after Iran amassed a large stockpile of highly enriched uranium. Here's what to know.

Tensions between the United States and Iran have caused an increase in oil prices across the country and here in New Jersey, according to experts.

The U.S. and Iran are signaling they're prepared for war if talks on Tehran’s nuclear program fizzle out, as a second U.S. aircraft carrier nears the Middle East.

President Trump has one bright red line for Iran's nuclear program and some areas of flexibility as he weighs military strikes or a possible deal in the coming days.

The gambit was successful. At least twice, the president weighed ordering an attack on Iran, only to be dissuaded by aides from moving forward. But America now appears to be on the brink of war with Iran again. And this time, instead of acting as a deterrent, the Pentagon’s war plans are being used to draw up options for the president to consider.

Washington has also demanded that Iran relinquish its stockpile of highly enriched uranium (HEU). The UN nuclear agency last year estimated that stockpile at more than 440 kg of uranium enriched to up to 60% fissile purity, a small step away from the 90% that is considered weapons grade.

Iran’s Revolutionary Guard Corps Navy launched the Sayyad 3-G naval air defense missile during exercises in the Strait of Hormuz as U.S. naval forces build up in the Gulf.