WASHINGTON (CN) - President Obama and Russian President Dmitry Medvedev signed a treaty in Prague Thursday reducing the nuclear arms of the two nations to the lowest levels in 50 years.
"Today is an important milestone for nuclear security and non-proliferation, and for U.S.-Russia relations," Obama said at the signing ceremony.
Medvedev said the treaty represents accomplishments reached by the two countries that a few months ago "seemed impossible."
Under the new pact, the two countries will reduce the number of nuclear arms from 2,200 to 1,550 each over the next seven years, a 30 percent reduction from current stores. In addition, they can have no more than 700 deployed launchers.
Together, the U.S. and Russia possess more than 90 percent of the world's nuclear weapons.
In conjunction with the signing, the Russian government made a unilateral statement that they would withdraw from the treaty if the United States aggressively built up its missile defense system. During treaty negotiations, Russia argued for measures that would limit missile defense, but the United States resisted.
The New Strategic Arms Reduction Treaty, or New START treaty, is an update to the original START treaty, signed in 1991 by President George H.W. Bush and Mikhail Gorbachev, which marked the end of the Cold War.
Once signed, the treaty has to be approved in the Senate by a two-thirds vote, or 67 votes.
The treaty signing precedes next week's nuclear summit in Washington. The agenda will focus on securing nuclear arms worldwide. Leaders from more than 40 countries are slated to attend, including Medvedev.
Obama has stated that he wants to see the complete eradication of nuclear arms worldwide, a goal he has said he will likely not see in his lifetime.
At a lunch celebrating the treaty, Obama called the treaty "one brick" on the path toward "a brighter future for all mankind."
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