WASHINGTON - " The Obama administration is adopting a new policy limiting the circumstances under which the US would use nuclear weapons, keeping with the president's pledge to give the nuclear arsenal a less prominent role in US defence strategy. In line with an in-depth review of US nuclear weapons policy, the administration also hopes to persuade Russia to agree to open talks on mutual cuts in nuclear arsenals that go beyond a new arms treaty to be signed this week, US officials said. The nuclear weapons policy review to be released Tuesday is the first since 2001. It would not radically change US policy, but officials said it will include language that reflects President Barack Obama's commitment to move toward a nuclear free world. By narrowing the conditions in which the US might use nuclear arms, Obama hopes to strengthen US arguments that other countries should either reduce stockpiles of nuclear weapons or forgo developing them. These officials said the administration's new nuclear policy would stop short of renouncing the use of nuclear weapons except in retaliation to atomic attack, as some activists have advocated. But it would describe the weapons' purpose as "primarily" or "fundamentally" to deter or respond to a nuclear attack. The document is expected to say the US is moving toward a policy in which the "sole purpose" of nuclear weapons is to deter or respond to nuclear attack, according to the officials who spoke on condition of anonymity because the policy review has not been released. That wording would rule out the use of such weapons to respond to an attack by conventional, biological or chemical weapons. Previous US policy was more ambiguous. In an interview with the New York Times on Monday, Obama said his administration was explicitly committing not to use nuclear weapons against non-nuclear states that are in compliance with the Nuclear Non-Proliferation Treaty, even if they attacked the United States with biological or chemical weapons. Those threats, he told the newspaper, could be deterred with "a series of graded options" -- a combination of old and newly designed conventional weapons.