* Japan Post to book 40 bln yen annual loss
* Will record 400 bln yen goodwill writedown on Toll Holdings
* Japan's M&A faces scrutiny after Toshiba debacle (Adds details on Japan Post earnings)
By Stanley White
TOKYO, May 12 (Reuters) - Japan Post Holdings will buy Nomura Real Estate Holdings to strengthen its presence in real estate development, national broadcaster NHK reported on Friday.
Japan Post is preparing to issue a tender offer, NHK said, citing unnamed sources.
Telephone calls to Japan Post and Nomura Real Estate were not answered.
If confirmed, the timing of the acquisition could raise eyebrows because Japanese companies have stunned investors recently with losses on M&A deals that have turned sour, which is raising questions about the quality of their due diligence.
Only last month Japan Post, which is 80 percent state-owned, announced a $3.6 billion writedown on its purchase of Australian logistics firm Toll Holdings Ltd.
That massive writedown saw Japan Post join the likes of Toshiba Corp in high-profile foreign takeover flops.
Japan Post has estimated it will announce a 40 billion yen loss in the year to March, its first loss in at least a decade, when it releases its earnings on Monday.
Japan Post's business spans from banking and insurance to parcel delivery, but limited growth in its domestic market has led the company to commit to growth through acquisitions.
However, the writedown on its purchase of Toll and Toshiba's accounting woes show the significant risks of this strategy. (Reporting by Stanley White; Editing by Randy Fabi and Elaine Hardcastle)