TOKYO, Nov 20 (Reuters) - Sumitomo Mitsui Finance and Leasing Co has agreed to buy a majority stake in Japanese property investor Kenedix Inc for 132 billion yen ($1.3 billion) to expand its property business, the companies said on Friday.

Sumitomo Mitsui Finance, a leasing unit of Sumitomo Financial Group Inc, aims to buy a 70% stake in Kenedix, a joint statement issued by the two companies said.

It added that Singapore-based ARA Real Estate Investors, Kenedix's top shareholder, is planning to boost its stake to 30%.

"Sumitomo Mitsui Financial has positioned property business as core for our sustainable growth and bigger corporate value, and we have been trying to strengthen this business," the leasing company said.

Kenedix has 2.5 trillion yen of assets under management, and is one of the most powerful independent property asset managers in Japan, according to the statement.

The bid comes shortly after Mitsubishi UFJ Lease agreed to acquire smaller rival Hitachi Capital Corp in September.

Sumitomo Mitsui Finance will offer 750 yen per share to Kenedix shareholders through a public tender offer, a 14.5% premium to Friday's close of 655 yen.

Sumitomo Mitsui Finance is half owned by Sumitomo Mitsui Financial Group and the other half by Sumitomo Corp.

($1 = 103.7600 yen) (Reporting by Junko Fujita and Chang-Ran Kim; Editing by Sherry Jacob-Phillips and Jan Harvey)