Like I asked before, how will they pay it back? You didn't answer bother to answer the question.
“And where would Ukraine get the money to pay it back, like Russia and the U.K. after WWII?”
Answer for your USSR & Great Britain example of
Lend-Lease Payback for WWII by USSR & Great Britain
1. USSR Repayment:
The U.S. asked for $1.3 billion to settle the debt, but was only offered $170 million by the USSR.
In 1972, the dispute remained when the U.S. accepted an offer from the USSR to repay $722 million linked to grain shipments from the U.S. With inflation, this only represented 25% of the initial debt with the remainder being written off.
2. Great Britain Repayment:
The final payment of $83.3 million (£42.5 million), was made by Britain on December 29, 2006. After this final payment, Britain’s Economic Secretary to the Treasury formally issued thanks to the U.S. for its wartime support.