RLPC-Four banks mandated to lead BG's Origin acquisition loan

LONDON, May 6 (Reuters) - Four banks have been appointed as mandated lead arrangers on the multibillion dollar syndicated loan to finance British gas producer BG Group Plc's (BG.L) $12.1 billion bid approach for Australian utility group Origin Energy (ORG.AX), senior bankers close to the deal said on Tuesday.

The four banks confirmed as leading the loan are HSBC, Royal Bank of Scotland, Societe Generale and Santander, the senior bankers said.

The size of the loan has not been revealed as the bid approach could yet attract a rival offer, sources added.

BG Group said last week it would finance the all-cash bid with a mixture of existing cash reserves and a syndicated loan.

The loan will be BG Group's debut syndicated loan, which will boost the appeal of the deal to banks looking to forge stronger relationships with the company, sources said.

A banker close to the deal said the loan's pricing and structure would be attractive to banks as they are compatible with difficult loan market conditions that are raising the cost of borrowing for companies.

BG, valued at around $86.5 billion, approached Origin with a proposal of A$14.70 per share in cash, a 40 percent premium to Origin's close of A$10.47 last Tuesday.

Origin is the largest holder of coal seam gas resources in Queensland. It is also Australia's only vertically integrated energy company, with oil and gas production assets accounting for about a quarter of its revenues, which have helped offset tighter margins in its traditional retail energy business. (Reporting by Tessa Walsh, editing by Will Waterman)