One of the foremost military leaders of Iran was killed in a US airstrike in the early hours of Friday in the latest escalation of tensions between Iran and the US. Last year Iran threatened

to accelerate its nuclear program this week, directly violating a nuclear agreement signed in 2015. Tensions between the US and Iran have neared breaking point over the past year after a

series of attacks on oil tankers and the most recent use of a missile to sink a US drone in “international airspace”. Both countries have warned of terrifying consequences if the other

attacks. But does Iran have nuclear weapons and could the country nuke the US? HOW DID CURRENT TENSIONS WITH IRAN START? Tensions between the US and Iran have risen and fallen since the

DID THE 2015 NUCLEAR PACT SAY? In 2015, Iran agreed a long-term deal on its nuclear programme with a group of world powers known as the P5+1, which includes the US, UK, France, China, Russia

and Germany. The deal came after years of tension over Iran's alleged efforts to develop a nuclear weapon.  Iran insisted that its nuclear programme was entirely peaceful, but the

international community did not believe that. Under the accord, Iran agreed to limit its sensitive nuclear activities and allow in international inspectors in return for the lifting of

crippling economic sanctions. Iran agreed to limit the enrichment of uranium, which is used to make reactor fuel but also nuclear weapons; redesign a heavy-water reactor being built, whose

spent fuel would contain plutonium suitable for a bomb; and allow inspections by a global watchdog. DON'T MISS US airstrikes updates as fears of World War 3 erupt over Iran [INSIGHT]

THE CHILLING IMAGE TRUMP SHARED AFTER ORDERING HORROR BAGHDAD ATTACK [PICTURES] WORLD WAR 3 PANIC - US AIRSTRIKE KILLS TOP IRANIAN COMMANDER [EXPLAINER] But since the US left the deal it has

imposed new sanctions, hitting Iran's economy and raising Iran-US tensions. Enriched uranium is used to make reactor fuel, but also nuclear weapons. Iran had two facilities - Natanz

and Fordo - where uranium hexafluoride gas was fed into centrifuges to separate out the most fissile isotope, U-235. Low-enriched uranium, which has a 3-4 percent concentration of U-235, can

be used to produce fuel for nuclear power plants.  "Weapons-grade" uranium is 90 percent enriched. In July 2015 at the time of the nuclear deal, Iran had almost 20,000

centrifuges. Under the nuclear deal in 2015, Iran was limited to installing no more than 5,060 of the oldest and least efficient centrifuges at Natanz until 2026 - 10 years after the

deal's "implementation day" in January 2016. On June 17, Iran announced it would exceed limits of stockpiled uranium set by the 2015 arrangement on June 27. The US withdrew

from the nuclear deal on May 8 this year, but despite this Iran has remained committed to the deal and to the other agreements within it, according to the International Atomic Energy Agency

(IAEA), which inspects Iran's nuclear sites and issues quarterly reports on its compliance. Iran does not yet have a fully equipped nuclear bomb, but with the stockpiled uranium the

country is heading in the direction of building a bomb.  As the country does not have nuclear weapons to hand, it is impossible for them to currently issue a full scale nuclear attack.

However, it is possible that Tehran could use its growing missile program to target American ships and troops in the area.