Talks involving representatives of Ukraine, the United States and Europe in Miami have ended earlier than planned, according to a senior correspondent from Radio Free Europe/Radio Liberty, an international media organization, on Saturday.

US Special Envoy Steve Witkoff said in a social media post on Friday that representatives from the United States, Ukraine and Europe had met that day in Miami, Florida, for "constructive" discussions on Ukraine's energy resilience, grain exports, security guarantees, and ways of ending Russia-Ukraine tensions before the start of winter.

The early conclusion of the talks came amid fresh strains in Kyiv-Washington relations. 

Ukrainian President Volodymyr Zelenskyy, during a recent interview, expressed clear disappointment and even a sense of betrayal by the news of the US-Russia diesel deal.

In a phone interview with Axios on Friday, he criticized US President Donald Trump's decision to unilaterally ease sanctions on Russia and permit its diesel exports, calling it "unfair and dishonest."

Trump said on Friday in a post on social media that he had agreed in a call with Russian President Vladimir Putin that Russia would immediately supply diesel to the US and global marketplace.

When asked repeatedly by reporters about Zelenskyy's criticism, he declined to comment, saying only that he was satisfied with the agreement he had reached with Russia.