What are President Zelensky's concerns about the US-Russia negotiations?

President Zelensky insists that Ukraine must be directly involved in any negotiations about its future, stating he will not agree to anything without Ukraine's presence at the talks. His concerns stem from the apparent direction of discussions, which seem to be leading toward a summit between Donald Trump and Vladimir Putin without adequate Ukrainian representation. Zelensky is particularly worried about Russia's maximalist demands requiring Ukraine to make territorial concessions and abandon its NATO ambitions. Despite American assurances of Ukraine's involvement, Zelensky remains concerned that decisions affecting Ukraine's sovereignty could be made without sufficient Ukrainian input.