Why is Trump making this demand ?
Because Trump know that this is the one thing that Zelensky cannot deliver so Trump is methodically smoking Zelensky out on the issue
Why you ask ?
Simple, because seizing control of the Ukraine's vast natural resources by the globalist foreign interests was a primary reason for the war and Zelensky has already sold those Ukrainian assets to his string pullers who engineered the war
And that is why the complicit fat cats in the US and the EU are squealing like stuck pigs whenever Trump brings up the issue
Trump is toying with these people and no doubt savoring their fear and distress as they watch their carefully laid plans evaporate before their eyes and they realize that they have engineered their own downfall instead of their intended targets. - America and Donald Trump
BINGO