STORY: The last remaining treaty that limits Russian and U.S. nuclear weapons was already in peril before President Vladimir Putin announced this week that Moscow was suspending its participation.

Now analysts say the New START treaty may be beyond repair, raising the risk of a new, global arms race.

“I read this as the New START treaty is pretty much dead.”

Heather Williams is the Director of the Project on Nuclear Issues and a Senior Fellow at the Center for Strategic and International Studies.

She says suspending the treaty cuts off an important line of communication between the two countries at a perilous moment when Putin is increasingly portraying the Ukraine war as a direct confrontation with the West.

"First and foremost that I think we really need to be conscious of is that this means the end of bilateral dialogue between the U.S. and Russia. New START was one of the few remaining forums for those bilateral discussions, particularly discussions that included defense officials, which, you know, is incredibly important in Russia right now because the Ministry of Defense is so influential. And so with the end of New START, we're not just losing an arms control agreement, we're losing a really important communication channel and we're losing that communication channel at the exact moment when we need it most, when nuclear risks are rising, when Putin is making all these nuclear threats. And so it really is a dangerous and irresponsible move on Putin's part."

U.S. President Joe Biden said Wednesday Putin’s decision was a big mistake, and pledged to defend every inch of NATO.

The treaty effectively limits the number of warheads per missile that either side can deploy, and it allows each side inspections every year to ensure the other has not breached the treaty's limits.

"It's important to acknowledge New START has been a really successful treaty. As of January, the two countries had conducted 328 inspections since 2010. This is a really big achievement. And so we're losing that transparency into the Russian arsenal, losing that predictability- it's going to be a lot harder to understand if and how Putin is expanding the arsenal. "

But the risks stretch beyond Russia and the West.

Putin’s move may also have dashed any hopes of dragging China to the table to start talking about its own rapidly accelerating nuclear arms programs.

"So in the short term, Putin's announcement to suspend New START gives China a free pass. China doesn't want to participate in arms control. China is opposed to really any transparency into its nuclear arsenal or into its nuclear doctrine. And if U.S.-Russian arms control is breaking down, it doesn't put any pressure on China to engage."

Putin said Wednesday China's Xi Jinping would visit Russia, raising concerns in the West that Beijing could provide weapons to support Russian's invasion of Ukraine, and lead to a potential escalation of the conflict.