U.S. to Propose New Phase In Nuclear Arms Cuts

WASHINGTON—President Barack Obama, in a major foreign policy speech in Berlin on Wednesday, is set to make the case for a new phase in nuclear weapons reductions, according to senior U.S. officials briefed on the plans.

Despite mounting tensions with Cold War adversary Russia over the Syrian civil war and missile-defense, Mr. Obama is expected in the speech to say that the U.S. and Russia can reduce their arsenals of deployed nuclear weapons by up to another one-third, beyond the cuts mandated under the 2010 New START, or Strategic Arms Reduction Treaty, without undercutting deterrence or capabilities, the officials said.

Though it is unclear whether Mr. Obama will spell out precisely how many warheads he wants to cut in the Berlin speech, the officials said the Obama administration believes Moscow and Washington can cut their arsenals to between 1,000 and 1,100 warheads, down from the new START limit of 1,550. That still would leave them with more than enough warheads to deter any current or future adversary, according to officials briefed on the plans.

Nuclear arms experts said Mr. Obama doesn't need to wait for a formal follow-on treaty to move on new reductions. The two presidents instead could achieve similar results, more rapidly, through parallel, reciprocal reductions of strategic warheads to well below 1,000 within the next five years. Such cuts could be verified under the 2010 New START treaty, experts said.