The situation is reminiscent of World War I's Inter-Ally war debt tangle. (michael-hudson.com)
This was quite an impressive feat when it was a fledgling nation with substantial war debts. (politics.stackexchange.com)
I think the only ones are the British, who on one occasion unilaterally reduced the coupon and on another (after WWII) converted war debt into perpetuals. (nakedcapitalism.com)