Political scientist Oleksii Buriachenko stated this on Espreso TV."What is needed for Putin to sit down at the negotiating table? Pressure is needed. The answer to this question is very simple. And it's real pressure, comprehensive pressure. Both on the battlefield, through military support for Ukraine with weapons, and through sanctions pressure. The more pressure there is, the closer Putin will come to realizing that he can no longer continue the war, and therefore will not be able to fulfill his political objectives. This is a very simple answer. But then it gets more complicated," he said.BurIachenko emphasized that Trump didn't just want to end the Russian-Ukrainian war."Trump was trying to solve both a local problem – to get the Nobel Peace Prize – and strategic problems. He was trying to strengthen his position before a bilateral contact with Xi Jinping, with China. And he wanted to have cards before this meeting, and pulling Russia away is, in principle, a pretty serious card. There's the Arctic, there are rare earths, there's the Nobel Peace Prize. And Trump doesn't hide this. He says directly in his interviews that he expected to end this war much faster because he had good relations with Putin, and they resolved issues together," the political scientist said.He recalled that Trump even promised this in his inaugural speech, thereby cornering himself into a certain political dead end."And now his own American media constantly ask him these questions: 'So what about ending the Russian-Ukrainian war?' And he is essentially forced to answer them. And now, when he imposed sanctions, when he realized that there isn't enough pressure on Putin right now for him to accept the ultimatum. He doesn't want to or can't – for various subjective and objective reasons – directly pressure him now to get him to the negotiating table. He did impose sanctions on Lukoil and Rosneft, which came into force on November 21. Now he definitely has something to tell journalists. And he can, so to speak, put this issue on hold. Putin is presented with a fork, saying, 'Look, either you accept my ultimatum by Christmas and take what I'm telling you absolutely seriously,'" Buriachenko believes.According to the political scientist, such a window of opportunity for ending the war indeed remains."Or it will indeed be postponed until later periods, when Putin begins to fully feel the pressure of these corresponding sanctions. But everything necessary for at least an interim meeting with Xi Jinping, Trump has now done. He didn't get the cards he wanted before the meeting, but he did get cards nonetheless. And it's no coincidence that this meeting took place at the Asia-Pacific Economic Cooperation summit, because it didn't involve the disclosure of any agreement, communiqué, or joint press conference. It took place not as a bilateral summit, but within the framework of a general summit. And the parties were solving their tactical problems. And accordingly, they all solved some, and postponed others until 2026," he said.Buriachenko emphasized that Trump, at the end of 2025, has maintained all his positions."He hasn't given up a single position. He is ready to continue communication with both the Russian Federation and China, but in both cases, through force. Therefore, as a conclusion, everything will now truly depend primarily on Putin. On how much he realizes that moving into 2026 will only make his position much, much worse. And if he doesn't do that, then unfortunately, he will go down the path of escalation against European NATO countries and, possibly, nuclear provocations somewhere, as a last resort. That is, unfortunately, if Putin cannot be brought to this negotiating table by Christmas, 2026 will certainly see an increase in mutual escalation," the political scientist concluded.