(Adds impact on NBG capital ratio)
By George Georgiopoulos
ATHENS, June 29 (Reuters) - Dutch insurance group EXIN agreed to buy a 75 percent stake in Greek lender National Bank's (NBG) insurance subsidiary for 718 million euros ($820.17 million), it said on Thursday.
NBG, Greece's second-largest bank by assets, 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.
Other Greek banks have been divesting assets and foreign subsidiaries. Eurobank has sold an 80 percent stake in its insurance unit Eurolife to Canada's Fairfax Financial Holdings for 316 million euros.
EXIN said the agreed price implied an enterprise value of 958 million euros for the unit.
"NBG will retain a 25 percent stake in Ethniki Insurance, which remains NBG's exclusive bancassurance provider under a new 10-year partnership agreement for life, savings and non-life insurance products." EXIN said.
EXIN Group was founded earlier this year with the backing of investor EXIN Partners and U.S. asset manager Calamos Investments, targeting reinsurance, wholesale and retail life insurance markets in Europe.
Its first deal was the purchase of AIG's shares in AIG- Greece in December last year.
EXIN said it shares a common ambition with NBG to develop Ethniki Insurance and substantially upgrade its core systems and processes to better serve customers.
EXIN will contribute distribution, technical, underwriting and digital expertise to the partnership, including its proprietary application and algorithm-based predictive behaviour technology.
UBS advised EXIN on the transaction.
NBG's board approved the sale to the American-Dutch consortium on Wednesday and will seek shareholder approval on Friday at a scheduled general assembly.
The bank said the sale would boost its core equity Tier 1 capital ratio by 110 basis points to 18.5 percent. It also agreed an exclusive deal in bancassurance under which NBG will distribute EXIN products via its network.
NBG CEO Leonidas Fragiadakis said the bank was "implementing its commitment to European authorities and shareholders".
Calamos-EXIN was competing against three interested Chinese groups interested in the unit: Fosun, Shanghai-based Gongbao and Wintime.
"The deal reinforces our commitment to the southern European financial services market as part of our strategy. EXIN has the expertise to lead a renaissance for the industry across the region," said Calamos Investments CEO John Koudounis.
NBG was advised by Morgan Stanley and Goldman Sachs on the divestment. (Reporting by George Georgiopoulos; editing by David Evans and Jason Neely)