Petroplus, Europe\'s largest independent oil refiner said its German susidiaries are to file for insolvency following its decision two days earlier to file for bankruptcy. Petroplus said in a statement \"its subsidiaries in Germany, Marimpex Mineraloel-Handelsgesellschaft mbH, Petroplus Deutschland GmbH, Petroplus Bayern GmbH, Petroplus Tankstorage Holding Deutschland GmbH and Petroplus Raffinerie Ingolstadt GmbH, which owns the Ingolstadt refinery, filed for insolvency proceedings.\" The Swiss-based oil refiner also announced that its subsidiaries in France, \"Petroplus Holdings France SAS, Petroplus Marketing France SAS, Petroplus Raffinage Reichstett SAS and Petroplus Raffinage Petit-Couronne SAS, which owns the Petit Couronne refinery,\" have filed for judicial assistance. Credit ratings agency Standard and Poor\'s on Wednesday downgraded the company\'s long-term debt rating by two notches to D or \"default\" classification citing its inability to pay off long-term debts. The ratings of Petroplus Europe\'s largest independent refiner dropped from its previous \"CC\", the day after it announced it was filing for bankruptcy due to its failure to reach agreement with its banks. Petroplus, with $1.75 billion (1.3 billion euros) in outstanding debt, had been negotiating for weeks with lenders to reopen credit lines needed to maintain operations, said last week it would sell its Petit Couronne refinery in France. Petroplus also said it was looking for strategic alternatives including the sale of its Cressier (Switzerland) and Antwerp (Belgium) refineries.