ZURICH, Sept 7 (Reuters) - A first insurance claim has been filed and more are being prepared in Credit Suisse"s (CSGN.S) efforts to recover funds from its insolvent supply chain finance linked to Greensill, the Swiss bank said on Tuesday. The collapse of Credit Suisse"s $10 billion worth of supply chain finance funds in March kicked off a tumultuous period for the bank, which together with a multi-billion dollar loss related to family office Archegos prompted a raft of executive oustings. "A first insurance claim has been filed and (Credit Suisse Asset Management) is currently preparing to file additional claims through Greensill Bank and with the assistance of Greensill Capital UK," the bank said in a document on its website. A spokesperson said no further information could be provided regarding the insurance claims at this time. Credit Suisse has been working with advisors and external experts to help recoup the funds, some $7.0 billion, or 70%, of which have now been recovered, the bank said on Tuesday, up from $6.1 billion in early July. read more Around $5.9 billion of that has been returned to investors so far after the last payment in August. read more Even so, the pool of late payments had grown during the period, with the bank saying roughly 85% of the outstanding notes related to payment that had not been made on time. As of end-August, the funds had accumulated some $2.5 billion in late payments, Credit Suisse said, $2.2 billion of which were related to three single counterparties, the biggest of them steel tycoon Sanjeev Gupta"s GFG Alliance, which are experiencing repayment issues. The bank expects the funds to accrue around $145 million this year in recovery costs, it said on Tuesday, as it focuses on some $2.3 billion in loans provided by Greensill to the three counterparties, GFG, Katerra and Bluestone. read more It said talks were ongoing regarding the refinancing and restructuring of GFG"s assets in the United States and Britain, while discussions with West Virginia governor Jim Justice"s coal company Bluestone Resources were unlikely to yield any payments or agreements before the fourth quarter. Tokio Marine"s (8766.T) Australian unit has provided insurance to speciality finance firm Greensill, but the Japanese group has said it is investigating the validity of those policies and, as of May, expected no material impact on its earnings from the matter.