I thought the WW1 debts went into hiatus around the chaos of WW2 (for us and others), with (according to the BBC, though it’s an old link) the govt position of “Neither the debt owed to the United States by the UK nor the larger debts owed by other countries to the UK have been serviced since 1934, nor have they been written off.” was the status quo, last I understood.
Also worth mentioning (not in response to you, but generally relevant to this subthread), was that the WW2 debt was actually finally paid off by the last Labour govt (Blair, with Brown as chancellor) - I seem to recall (but could be wrong) that prior to that everyone was pretty much happy to just service interest payments?
