Singapore's Oversea-Chinese Banking Corp has made an offer to buy Wing Hang Bank for HK$38.428 billion ($4.95 billion) after reaching a deal with major shareholders including the founding family of the Hong Kong-based lender.

The deal was the outcome of months of negotiations, with the deadline for an agreement extended twice. The acquisition, OCBC's biggest, would give Singapore's second-largest bank a much sought-after gateway to the Greater China region, where it earned 6 percent of its pre-tax earnings in 2013.