The U.S.’s largest automaker, General Motors Co., is preparing a bid for Ally Financial Inc.’s auto-lending arms in Latin America and Europe, according to anonymous sources close to matter. GM is not pursuing Ally’s Mexican auto insurer or its Canadian operations.

Ally put its non-U.S. operations on the sales block in May to help the Detroit-based company repay a U.S. government bailout. Sources say there were nearly 30 interested buyers in July, and bids had to be submitted by Sept. 21.

Such a purchase by Detroit-based GM Financial, which was created in 2010 following the acquisition of AmeriCredit Corp., would more than double its assets. GM owned Ally’s predecessor, GMAC, until 2006 when Cerberus Capital Management LP bought 51%.

GM has steadily grown since its inception, originally purchasing AmeriCredit in an effort to raise car sales by offering customers more credit options. The company bought FinanciaLinx Corp. in Toronto in 2011 to boost its Canadian operations.

With GM’s focus mostly on the North American market, Ally financed roughly 30 percent of GM’s international customers in 1Q12. Ally’s European and Latin American lending arms had $16.4 billion of assets.

As of June 30, the financial unit of GM had $14.6 billion of assets.