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ATHENS, June 27 (Reuters) - The board of Greece's National Bank (NBG) approved the sale of a majority stake in the group's wholly-owned insurance subsidiary to American-Dutch consortium Calamos-EXIN, a banker close to the deal told Reuters on Tuesday.
NBG is selling the unit as part of a restructuring plan approved by the European Union to exit non-banking operations and focus on core banking.
"The board gave its green light to the sale," the banker said.
The banker did not disclose details of the agreed sale price or other terms. Details are expected to be announced at the bank's annual meeting on Friday.
U.S.-based Calamos Investments, which has $20 billion under management, and EXIN Partners, a Netherlands-based investor focused on insurance, reinsurance and asset management, were bidding for at least 75 percent of National Insurance.
Calamos-EXIN was competing against three interested Chinese groups: Fosun, Shanghai-based Gongbao and Wintime.
Founded in 1891, National Insurance is Greece's oldest insurer and provides life and non-life insurance products. The company had a 16.6 percent share of the market last year and 2015 net profit of 98 million euros ($110.53 million).
Calamos Investments CEO John Koudounis told Reuters last month Calamos-EXIN had put forward a hard-to-match bid but did not provide details. He said other Greek-American investors interested in Greece were watching closely.
National Bank, which is 40 percent owned by Greece's HFSF bank rescue fund, will seek shareholder approval for the sale at Friday's annual meeting.
NBG was advised by advised on the divestment by Morgan Stanley and Goldman Sachs.
Exin Partners bought insurer AIG-Greece from AIG in December, partnering with Canellopoulos Adamantiadis Insurance Agency. ($1 = 0.8866 euros) (Reporting by George Georgiopoulos; Editing by Adrian Croft)