In 1990 Polish intelligence conducted an operation assisting in the withdrawal of six American operatives (a mix of CIA and DIA officers) investigating Iraqi troops movements in Iraq before the Gulf War. en.wikipedia.org/wiki/Operation_Simoom
After the operation was over and successful the Americans asked 'what do you want from us'? Poland answered nothing, 'at least let us pay for your operational costs', again the answer from the Polish side was, no. As a reward CIA director Webster during his visit to Poland forgave half of Poland's debt to the United States, 20 billion dollars:
With gratitude to the head of the CIA left Mazowiecki letter in which he reduced the Polish debt to the United States by half , or $ 20 billion - says gen. Gromosław Czempiński , Polish spy , one of the main characters of operation " Simoom " .