LISBON, May 4 (Reuters) - Portugal’s state-backed Resolution Fund wants to negotiate a large loan from a group of banks to shore up the capital of lender Novo Banco, which was carved out of the collapsed Banco Espirito Santo (BES). Such a cash injection is politically contentious, however, partly because loss-making Novo Banco is 75%-owned by U.S. private equity firm Lone Star. The remaining 25% is owned by the Resolution Fund. “The possibility of a loan from a syndicate of banks of the national banking system is on the table,” Bank of Portugal Governor Mario Centeno told a news conference late on Monday. Centeno, a former finance minister, did not provide further details on the size or timing of the capital injection into the country’s third-largest bank. “We must wait,” he said. The Resolution Fund is backed by all Portuguese banks which pay annual contributions to finance it, and it can access loans from the state. Lone Star acquired the majority stake in Novo Banco in 2017, with the sale contract stipulating that the Resolution Fund must inject up to 3.9 billion euros if certain losses occurred from the sale of toxic assets inherited from the collapsed BES. The injection is meant to keep the bank’s solvency ratios at the required levels. During the same news conference on Monday, Resolution Fund head Luis Maximo dos Santos said the fund did not have enough funds to meet its obligations and was still “carrying out the checks required to do all capital injections”. According to dos Santos, negotiations with the group of banks were “complex”. Novo Banco has been offloading bad loans, real estate and non-core assets under restructuring commitments agreed with Brussels, and the resolution fund has already injected 3 billion euros into the bank to cover those losses. Opposition parties are against injecting cash into Novo Banco and last November blocked a government proposal for the resolution fund to inject an extra 476 million euros. Opposition lawmakers fear Novo Banco could be benefiting Lone Star by selling it non-performing assets at discounted prices, which would inflate the lender’s losses. Under the terms of the sales contract, Novo Banco is not allowed to sell assets to Lone Star or entities related to it. Novo Banco and Lone Star have denied any wrongdoing. Lone Star has said it has never been part of any type of transaction with related parties for the acquisition of assets, including real estate assets, from the Novo Banco group. (Reporting by Sergio Goncalves; Editing by Catarina Demony and Pravin Char) Our Standards: The Thomson Reuters Trust Principles.