SoftBank Group Corp.’s Vision Fund accused Credit Suisse Group AG of shifting the blame over claims the investment group was responsible for losses the Swiss lender’s clients suffered from the collapse of finance firm Greensill Capital, according to documents seen by Bloomberg.

The documents, which include an internal memo and a letter sent to Credit Suisse’s lawyers, show that SoftBank’s leadership views the bank’s imminent suit as a "highly damaging publicity campaign” being run against them. The internal communications come ahead of an anticipated U.K. suit.

Credit Suisse is trying to reclaim $2.7 billion in overdue loan payments from borrowers including Katerra Inc., a U.S.-based construction company in which SoftBank was a major investor.