To reduce nuclear arsenals, President Medvedev and I signed the historic new START treaty —- not only committing our two nations to significant reductions in deployed nuclear weapons, but also setting the stage for further cuts and cooperation between our countries.

To move beyond outdated Cold War thinking and to focus on the nuclear dangers of the 21st century, our new Nuclear Posture Review reduces the role and number of nuclear weapons in our national security strategy. And for the first time, preventing nuclear proliferation and nuclear terrorism is at the top of America’s nuclear agenda, which reaffirms the central importance of the Nuclear Non-Proliferation Treaty.

And next month in New York, we will join with nations from around the world to strengthen the NPT as the cornerstone of our global efforts to prevent the spread of nuclear weapons even as we pursue greater civil nuclear cooperation. Because for nations that uphold their responsibilities, peaceful nuclear energy can unlock new advances in medicine, in agriculture, and economic development.

All of these efforts are connected. Leadership and progress in one area reinforces progress in another. When the United States improves our own nuclear security and transparency, it encourages others to do the same, as we’ve seen today. When the United States fulfills our responsibilities as a nuclear power committed to the NPT, we strengthen our global efforts to ensure that other nations fulfill their responsibilities.

So again, I want to thank my colleagues for making this unprecedented gathering a day of unprecedented progress in confronting one of the greatest threats to our global security. Our work today not only advances the security of the United States, it advances the security of all mankind, and preventing nuclear proliferation and nuclear terrorism will remain one of my highest priorities as President.