WARSAW (Reuters) - U.S. General Electric (GE) will seek compensation for any losses incurred by its Polish arm Bank BPH because of the planned conversion of Swiss-franc denominated mortgages into zlotys, which is being decided by the Polish parliament.

In a letter sent Polish authorities, signed by GE Capital chief executive Keith Sherin, GE said it saw further potential damage to BPH, following a 10-percent decline in the shares of BPH on the day the bill on the conversion was preemptively passed by the lower house of parliament.

"The GE Group intends to seek full compensation for any damage caused by the adoption and signing of the bill," the letter, published online by the Polish Senate read.

The lower house of parliament passed a draft law this month that would allow 47 percent of franc mortgage holders to convert their loans to zlotys at the banks' cost. The bill will now be voted by Senate and return to the lower house.

(Reporting by Pawel Sobczak, Adrian Krajewski, and Jakub Iglewski; Editing by Marcin Goettig)