Days before meeting Vladimir Putin in Alaska, Donald Trump referred to what he called "land swaps" as a condition for peace.

For Ukrainians, it was a confusing turn of phrase. What land was to be swapped? Was Ukraine to be offered part of Russia, in exchange for the land Russia had taken by force?

As Volodymyr Zelensky prepares to travel to Washington on Monday to meet Trump, there is likely no "swap" element to the US president's thinking.

Instead, he is reportedly planning to press Zelensky to surrender the entirety of the eastern Ukrainian regions of Donetsk and Luhansk in return for Russia freezing the rest of the front line – a proposal put forward by Putin in Alaska.

Luhansk is already almost entirely under Russian control. But Ukraine is estimated to have held onto about 30% of Donetsk, including several key cities and fortifications, at a cost of tens of thousands of Ukrainian lives.