How can you hold national elections when a good chunk of your country is under foreign occupation? It wouldn’t be a national election. It would be like holding a national election here in the US, but without Texas participating because Mexico has occupied it and claimed it. If you go ahead and hold the election anyway, you are tacitly accepting that Texas is no longer part of the US.
Those areas had their election last fall. Those elections won’t be reversed until NATO physically takes those areas back. Of course, who would care after the world war started by such a reckless attempt? Bottom line, Zelensky outlawed elections in the areas that now constitute Ukraine. I would expect the US administration and its stooges to approve and to give Zelensky cover with this bogus line.