Story highlights "Is there anyone that believes that North Korea would agree to a ban on nuclear weapons?" Haley asked

President Barack Obama's administration also opposed the talks

United Nations, New York (CNN) US Ambassador to the United Nations Nikki Haley announced Monday that the United States and almost 40 other nations would not participate in the first-ever talks on an international treaty to ban nuclear weapons.

Flanked by ambassadors from about 20 nations, including nuclear powers United Kingdom and France, Haley couched the decision not to attend the talks, which began Monday, in personal terms.

As a mom and daughter, "there is nothing I want more for my family than a world with no nuclear weapons," the former South Carolina governor said. "But we have to be realistic."

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"Is there anyone that believes that North Korea would agree to a ban on nuclear weapons?" Haley asked.

President Barack Obama's administration also opposed the talks, which the General Assembly voted to approve in December, and nuclear powers Russia and China also are not taking part. United Kingdom Ambassador Matthew Rycroft said his country also would not attend the talks because "we do not believe that those negotiations will lead to effective progress on global nuclear disarmament."

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