DUBAI, Dec 29 (Reuters) - National Bank of Oman (NBO) said on Thursday it had received a letter from Treasure Fleet International proposing to buy a stake in Oman's third biggest lender.

NBO will review the proposal; no legally binding commitments have been made and any deal would be subject to approval by shareholders and regulators, it said in a bourse statement.

The bank did not provide any further details about the proposed acquisition.

NBO is Oman's third largest lender by assets after Bank Muscat and Bank Dhofar. Treasure Fleet International is a Singapore-based firm, according to the company's website, which is incomplete and gives no details of the company's business.

SGPBusiness.com, a Singapore business directory, says Treasure Fleet International was incorporated as a limited exempt private company in August this year.

(Reporting by Alexander Cornwell; Editing by Andrew Torchia) ((Alexander.Cornwell@thomsonreuters.com;))