Backgrounder: Arms reduction treaty negotiations

As the US and Russia come closer to a new arms reduction treaty, we look at how negotiations have progressed thus far.

A year ago, the former Cold War rivals began negotiating on a new treaty to reduce nuclear arsenals.

The first round of talks was staged in May 2009 in Moscow. The two sides reached consensus in principle two months later.

However, disagreements emerged in who should reduce more nuclear warheads and how many kinds of weapons should be included in the reduction.

Different opinions led to a halt in negotiations. February 1st, talks reopened in Geneva, and a final agreement was reached in late March.

Vladimir Ryzhkov, Former Deputy President of State Duma, said, "I think that new treaty between Russia and the US is very important for the world to keep control of the nuclear technologies especially military technologies."

Thousands of nuclear warheads are deployed in the two countries, a legacy of their arms race. The new treaty limits the number to 1,550, a third of the original 1991 Strategic Arms Reduction Treaty.

Both presidents say the new cut in the largest arsenals on the planet are a step toward a world without nuclear weapons, and a signal to nations seeking them that there is no need.