Zelensky's office issued a carefully worded statement earlier on Thursday, saying the plan "in the American side's assessment, could help reinvigorate diplomacy".
In August Trump came away from a face-to-face meeting with Russian President Vladimir Putin in Alaska empty-handed. The US president became increasingly frustrated with negotiations with Moscow, culminating in Trump imposing fresh sanctions on Russia's two biggest oil producers which come into force on Friday.
Zelensky has been careful not to publicly criticise or reject the plan, saying he "appreciated the efforts of President Trump and his team to return security to Europe" – perhaps a way to keep the US president onside despite his administration's apparent soft approach to Russia.
But he stressed that Ukraine needs a "worthy peace," and that the "dignity of the Ukrainian people" must be respected.
The statement came after a meeting in Kyiv on Thursday between Zelensky and senior US military figures, including US Army Secretary Dan Driscoll, army chief of staff Gen Randy George and top US army commander in Europe Gen Chris Donahue.
When asked if Europe was involved in the process of drafting the plan, EU foreign policy chief Kaja Kallas said: "Not that I know of."
She added: "For any plan to work, it needs Ukrainians and Europeans onboard."
Ukraine's European allies have now had to take on much of the funding for Kyiv's military and financial aid, and countries including the UK and France have offered to provide forces to ensure any peace holds.
Moscow, meanwhile, has downplayed the significance of the 28-point plan.
Kremlin spokesman Dmitry Peskov said that, while there had been "contacts" with the US, there was "no process that could be called 'consultations'".
Peskov warned that any peace deal would have to address the "root causes of the conflict" - a phrase Moscow has used as shorthand for a series of maximalist demands which, to Ukraine, are tantamount to surrender.
Since starting his second term earlier this year, Trump has launched into various initiatives aimed at ending the war in Ukraine including several visits by his envoy Steve Witkoff to Moscow, and rounds of talks with Zelensky and other Western leaders.
But as the fourth anniversary of Russia's full-scale invasion of Ukraine nears, the two sides remain deeply at odds over how to end the conflict.
While Ukraine has become adept at targeting Russian military infrastructure and energy facilities with long-range drones, Moscow's attacks on Ukrainian targets continue unabated.
Late on Thursday, a Russian attack on the Ukrainian city of Zaporizhzhia killed at least five people, according to the regional governor. Hours later, Russia's defence ministry said it had intercepted and destroyed 33 Ukrainian drones over several Russian regions.
Earlier this week, at least 26 people were killed in a Russian missile and drone attack on blocks of flats in Ukraine's western city of Ternopil. Another 17 people were still missing at the site on Thursday, Zelensky said.