Ukraine on Tuesday agreed to a preliminary proposal put forward by the Trump administration that called for a 30-day ceasefire contingent on Russia's acceptance of the terms in a major step toward ending the brutal war.

But even if the Trump administration is able to get Moscow to the negotiating table and end the three-year war under a new treaty, which several security experts say Russian President Vladimir Putin is under no real pressure to do, can the Kremlin chief be trusted?

Russia under Putin has repeatedly violated formal international agreements intended to protect Ukraine’s sovereignty, chiefly from its former Soviet overlord.

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These agreements include the 1994 Budapest Memorandum, in which Ukraine agreed to relinquish its nuclear arsenal in exchange for assurances over its territorial integrity after its 1991 withdrawal from the Soviet Union, as well as the 1997 Treaty on Friendship, Cooperation, and Partnership by which Moscow and Kyiv agreed to respect one another’s existing borders. Both deals were first violated in 2014 when Putin seized Crimea and backed Russian separatist forces in the Donbas region. 

The 2014-2015 Minsk Agreements, though criticized as "weak," attempted to end Russia’s aggression in eastern Ukraine, an agreement that was never fully achieved and was again violated by Putin's 2022 invasion. 

Some world leaders and security officials, including Ukrainian President Volodymyr Zelenskyy, have cautioned that a peace deal between Russia and Ukraine is unlikely to be achieved in the near term and against Putin’s reliability in adhering to any international agreement without serious security commitments from the West.

"The problem here is that the Russians only understand win-lose outcomes, which means that to prevent them from ever attacking Ukraine again, they must see themselves to be the losers in the war just as they did at the end of the Cold War," Michael Ryan, former deputy assistant secretary of Defense for European and NATO Policy and former acting assistant secretary of Defense for International Security Affairs, told Fox News Digital.

Security officials interviewed by Fox News Digital argued that securing Ukraine’s future is not about "trusting" Putin. It’s about actually putting Russia in a position where any future violations would hinder Moscow more than it could be enticed by unchecked opportunity.

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"Even if a deal is concluded, Russia will continue clandestine operations across the world to expand its footprint in terms of geopolitical influence," Rebekah Koffler, a former DIA intelligence officer, told Fox News Digital, noting the former KGB operative can be counted on to "continue election interference campaigns, cyber warfare, espionage and destabilization operations across the globe.

"There’s no such thing as peace in Russia’s strategic military thinking. You are in a constant confrontation."

Ryan argued a Trump-brokered peace deal needs to reflect on the lessons learned from previously failed agreements, like the post-WWI Treaty of Versailles, which arguably led to the rise of Adolf Hitler and Nazi Germany.

"How to solve this conundrum? Just as we did after World War II … reconstruction of Ukraine must include economic reconciliation with Russia," Ryan said. "The Russians saw how we rebuilt the losing side in World War II Germany and Japan. They expected us to do the same for Russia after the Cold War, but we did not.  

"We can't make that same mistake if we want lasting peace for Ukraine and if we want to split Russia from China," he added, noting other adversaries are watching how the West handles this geopolitical hurdle.

There are numerous obstacles when it comes to the Trump administration’s attempt to negotiate with Putin, including arguments over occupied territory, international recognition of occupied lands, international aid and support for Ukraine, international confiscation of frozen Russian assets, Zelenskyy’s standing at home, the return of prisoners of war and the return of abducted Ukrainian children, according to Peter Rough, senior fellow and director of the Center on Europe and Eurasia at the Hudson Institute.

"Putin has officially annexed four Ukrainian oblasts as well as Crimea. But Moscow has yet to conquer any of the four entirely," Rough told Fox News Digital while traveling to Ukraine. "I can’t imagine that Ukraine will withdraw from the areas they control, having fought tooth and nail to defend those regions. 

"I also doubt that the West will offer de jure recognition to the areas Moscow controls," he added. "So, Putin would have to swallow all of that in a peace deal."

Each issue alone is a massive undertaking to negotiate, and while Ukraine this week may be outlining concessions it could make to secure a deal coordinated by the U.S., Putin is unlikely to do the same, according to Koffler, who briefed NATO years ahead of the 2022 invasion on Putin’s plans.

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"Putin is unlikely to make any concessions as he believes he is in a strong position," Koffler told Fox News Digital. "The disparity in combat potential dramatically favors Russia over Ukraine, which is out-manned and outgunned because Putin transitioned the Russian military and economy on a wartime footing seven years prior to the invasion of Ukraine."

"Putin believes he has prepared Russia to fight till the last Ukrainian and till the last missile in NATO’s arsenal," she added, echoing a January warning issued by NATO Secretary-General Mark Rutte, who said Russia’s defense industry output over a three-month period equates to what all of NATO produces an entire year.

"Putin is highly unlikely to agree to a ceasefire because he doesn’t want to give a strategic pause to Ukraine, the U.S., and NATO to re-arm," Koffler said. "He doesn’t trust Washington. He doesn’t trust President Trump any more than we trust Putin. 

"He trusts Trump even less than Biden because he could read Biden and predict his behavior. He cannot read Trump because Trump is unpredictable."

The experts argued there are too many variables that could play out during negotiations that will determine whether Putin can be adequately held accountable or "trusted" regarding future agreements.

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Ultimately, Koffler said, Putin will not leave eastern Ukraine.

"Ukraine has always been a red line for Putin, in terms of who has geopolitical control of it, Russia or the West. And he will continue to enforce this red line," she said. "The only way to ensure that Putin doesn’t invade another country is to make NATO strong again, beef up force posture, increase defense spending, secure its command-and-control networks and develop actual deterrence and counter-strategy that addresses every prong of Putin’s strategy."