U.S. Secretary of State Marco Rubio met with Ukrainian and key European officials in Geneva on Monday in a high-stakes diplomatic push to advance a 28-point American peace plan aimed at ending the war in Ukraine.

The proposal, which has stirred unease among some of Kyiv's allies and U.S. lawmakers, is reported to include provisions for potential territorial concessions to Russia. The meeting represents the most significant effort to date by the Washington administration to position itself as a central broker in negotiations to resolve the conflict.

Following a full day of closed-door talks, Secretary Rubio struck an optimistic tone. "We have had very productive and candid discussions today," Rubio told reporters. "The path to peace is difficult, but I am more confident than ever that a framework for a lasting resolution is within reach."

Ukrainian President Volodymyr Zelenskyy, in a statement from Kyiv, confirmed that the talks had made "substantive" progress, a carefully chosen term that suggests meaningful negotiation beyond preliminary discussions.

Despite the forward momentum, the emerging U.S. plan has been a source of significant concern. Leaked details suggesting that the proposal would involve Ukraine ceding occupied territories to Russia in exchange for a ceasefire and security guarantees have alarmed nations in Eastern Europe and drawn bipartisan criticism in Washington. Critics argue that such a move would reward Russian aggression and violate fundamental principles of international law.

In an apparent effort to address these concerns, a joint statement was released by the U.S., Ukrainian, and European delegations following the talks. The statement emphasized that any final agreement "must uphold Ukraine's sovereignty and territorial integrity within its internationally recognized borders" and ensure a "sustainable and just peace."

The inclusion of "internationally recognized borders" in the joint communiqué appears to be a key concession to Ukraine, seemingly at odds with the reports of territorial concessions. This discrepancy points to the delicate diplomatic tightrope the parties are walking and suggests the most contentious points of the U.S. plan remain unresolved.