The world's nuclear arsenal

Who will be next to join the nuclear power club?

India and Pakistan's nuclear tests have changed the map of nuclear-haves and nuclear have-nots. Once considered threshold nuclear states, they have now crossed over that line, and entered new territory.

Unlike the other nuclear powers, neither country has signed the Comprehensive Test Ban Treaty (CTBT), which bans nuclear test explosions, or the Nuclear Non-Proliferation Treaty (NPT), which obliges the nuclear powers never to transfer their nuclear technology to other countries, and forbids other countries from acquiring nuclear capability.

But many commentators say that the most dangerous ramification of India and Pakistan's tests is the encouragement they have given to other aspirant nuclear powers.

The nuclear power club

There are five countries who have admitted to having nuclear weapons and signed the CTBT and the NPT.

• United States Set off first nuclear blast in 1945. Conducted over 1,030 tests. Arsenal of 12,070 warheads. Missile range of 8,100 miles.

• Russia First test in 1949. Conducted 715 tests in total. Arsenal of 22,500 warheads - but shrinking. Missile range of 6,800 miles

• Britain First test in 1952. Conducted 45 tests in total. Arsenal of 380 warheads. Missile range of 7,500 miles.

• France First test in 1960. Arsenal of 500 warheads. Missile range of 3,300 miles.

• China First test in 1964. Conducted 45 tests, and helped Pakistan develop its nuclear capabilities. Arsenal of 450 warheads. Missile range of 6,800 miles.

Threshold States

Since Pakistan and India carried out their nuclear testing, openly declaring themselves to be nuclear powers, Israel is the only country left in this category.

• Israel Known to have nuclear weapons capability, but has never declared it or tested. It has an estimated arsenal of 100 warheads and a missile range of 940 miles.

Suspected nuclear aspirants

These countries have all signed the NPT, but they are nevertheless suspected of secretly trying to develop their own nuclear arsenals.

• North Korea Suspected of developing a nuclear bomb, and might have two warheads. Activity at its Yongbyon nuclear research centre was frozen under 1994 agreement with the US. Its missile range is 600-900 miles.

• Iran Suspected of being within 5-10 years of producing a nuclear bomb. Seeking to recruit Russian nuclear scientists. Missile range 310 miles.

• Iraq Before Gulf War was two years from producing bomb. Saddam Hussein has fought off United Nations weapons inspectors since 1991. Missile range up to 470 miles.

• Libya Despite numerous attempts to obtain nuclear weapons and technology, is thought to have made little progress. Missile range 190 miles.