National Security Adviser Robert O'Brien said in a statement on Friday that Vladimir Putin's position for the extension the New START treaty was a "non-starter" — effectively confirming that hopes of a pre-election nuclear deal had been dashed.

Between the lines: Just a few days ago, senior administration officials were expressing confidence that a deal was close, or even agreed in principle. But senior Russian officials, including Putin, have since indicated that they see little chance of a complex deal on such an expedited timetable.

• Putin instead proposed a one-year extension of New START, the last major bilateral deal constraining both nuclear superpowers, on Friday to allow for “substantive talks" on the future of arms control.

In response, O'Brien said the U.S. had already proposed a one-year extension "in exchange for Russia and the United States capping all nuclear warheads during that period."

• "This would have been a win for both sides, and we believed the Russians were willing to accept this proposal when I met with my counterpart in Geneva. President Putin’s response today to extend New START without freezing nuclear warheads is a non-starter."
• "The United States is serious about arms control that will keep the entire world safe. We hope that Russia will reevaluate its position before a costly arms race ensues," he said.

State of play: Russia ideally wants to extend New START, which expires on Feb. 5, for five years, the maximum duration set out under the original treaty.

• The Trump administration is skeptical of the Obama-era accord, but said it would extend it if for a shorter period if the Russians agreed to a nuclear warhead freeze and a framework for future nuclear negotiations that would also involve China.
• Yes, but: Joe Biden has also said he plans to extend New START shortly after taking office if he wins the election.

The bottom line: It appears that the Russians are willing to wait and see what happens on election day.