* Battle for Hong Kong mid-sized banks heats up
* OCBC does not have big presence in China
* China's AgBank does not have big presence outside China
* Chong Hing shares suspended ahead of merger announcement
By Denny Thomas and Saeed Azhar
Oct 23 (Reuters) - Singapore's Oversea-Chinese Banking Corp Ltd has joined other suitors in weighing a bid for Wing Hang Bank Ltd, one of four Hong Kong family-run lenders well positioned as a gateway between mainland China and the wider world.
OCBC is weighing an offer, said a person with direct knowledge of the matter. Agricultural Bank of China Ltd , China's No. 4 bank, is also considering a bid for Wing Hang, which has a market value of about $4.5 billion, people familiar with the matter told Reuters on Wednesday.
China's economic clout and the growth of the offshore yuan fixed-income market has made Hong Kong's mid-sized banks attractive to foreign lenders looking for a foothold on the mainland and for mainland Chinese banks seeking to branch out beyond their home turf.
Other potential suitors include Australia and New Zealand Banking Group Ltd, Australia's No. 4 bank, and Singapore's third-biggest lender United Overseas Bank Ltd , sources have said.
OCBC, Singapore's No. 2 lender by assets, is rated by analysts as one of Asia's strongest bank with Tier 1 capital ratio of 14.9 percent.
But it has lagged domestic rival DBS Group Holdings Ltd in North Asia. DBS's Hong Kong unit, which was formed through an acquisition, is the fifth-biggest bank in the commercial city.
OCBC earned just 5 percent of its first-half core profit from Greater China, while Singapore accounted for 61 percent.
For China's AgBank, a successful bid would be its first major acquisition outside its home market since a record-breaking IPO three years ago and one that could help it catch up with other state-run rivals.
While such a purchase would put a dent in the bank's cash pile, it would beef up its onshore and offshore deposit base. AgBank currently has just six overseas branches. Bank of China, by comparison, is in 36 countries.
The news comes as Chong Hing Bank Ltd, another Hong Kong-based family-run bank, nears a deal to be bought by Yue Xiu Group, a trading arm of China's Guangzhou city government, Reuters reported on Wednesday.
Chong Hing's shares were suspended on Thursday pending a merger announcement.
Wing Hang Bank's controlling shareholders said last month they had received preliminary offers from independent third parties which they did not name, putting the bank in play. Hong Kong's Fung family and BNY International Financing Corp jointly own about 45 percent of the bank.