MELISSA BLOCK, HOST:
The United States added a signature to a new treaty today. It's on international arms trade. The agreement is meant to stem the flow of weapons to conflict zones around the world. Human rights activists are hailing the decision, but the Obama administration will have an uphill battle getting the treaty ratified by Congress. NPR's Michele Kelemen has more from the United Nations.
MICHELE KELEMEN, BYLINE: Secretary of State John Kerry says he signed the arms trade treaty because he believes that when the U.S. works with others on these issues, the world is a safer place.
SECRETARY JOHN KERRY: This is about keeping weapons out of the hands of terrorists and rogue actors. This is about reducing the risk of international transfers of conventional arms that will be used to carry out the world's worst crimes.
KELEMEN: He's already facing opposition from his former Senate colleagues. The ranking Republican on the Foreign Relations Committee, Bob Corker of Tennessee, says the administration can't implement the arms trade treaty without congressional approval. Kerry says it mainly builds on export controls the U.S. already has in place and ensures that other countries follow similar practices.
KERRY: We are talking about the kind of export controls that, for decades, have not diminished one iota our ability in the United States as Americans to exercise our rights under the Constitution.
KELEMEN: The president of Oxfam American, Ray Offenheiser, was among the activists on hand for today's signing ceremony at the U.N. headquarters.
RAY OFFENHEISER: It's a tremendous victory for the human rights community and the humanitarian community because, in many ways, it focuses on limiting the flow of illicit arms around the world that are actually driving atrocities and human rights violations.
KELEMEN: The treaty will go into force once more than 50 countries ratify it and Offenheiser hopes that will occur by the end of next year. He says he is realistic about the chances for ratification in the U.S., but says the simple fact that the U.S. signed it is important.
OFFENHEISER: We are the largest exporter of arms in the world. And I think many of the countries that are here today in New York are watching what the United States is doing and the fact that the United States is here and is signing, I think, is actually encouraging many other countries to sign.
KELEMEN: Other activists have also raised hopes that the U.S. will now be in a stronger position to encourage Russia to stop arming Bashar al-Assad's regime in Syria. Russia abstained from the vote on the arms trade treaty. The countries that voted against it include Syria, Iran and North Korea.
Michele Kelemen, NPR News, the United Nations. Transcript provided by NPR, Copyright NPR.