Nine countries currently either say they have nuclear weapons or are believed to possess them. The first to have nuclear arms were the five original nuclear weapons states — the United States, Russia, China, France and the United Kingdom.

President Trump said Monday that he disagrees with Director of National Intelligence Tulsi Gabbard's assessment from a few months ago that Iran is not currently trying to build a nuclear weapon and has not been doing so since 2003.

Americans strongly support preventing Iran from acquiring nuclear weapons according to Reagan Institute poll, as Trump reiterates stance amid Israel-Iran conflict

Tulsi Gabbard gave official details while speaking at the US House Congress. However, the claims have been rejected by President Donald Trump.

China has an estimated 600 nuclear warheads—an increase of 100 in just one year—the Stockholm International Peace Research Institute reported.

Israel strikes Iran's nuclear facilities, but an expert cautions that the heavily protected Fordow site remains a dangerous threat that only U.S. military capabilities can neutralize.

Only the U.S. military has the 30,000-pound bomb capable of reaching the facility and the bomber that can carry it.