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Oct 31 (Reuters) - British supermarket Sainsbury's SBRY.L said it has sold its Argos Financial Services cards portfolio to NewDay Group for an expected 720 million pounds ($934 million) in line with its strategy to focus on its core retail business.

Britain's second largest supermarket group after Tesco said on Thursday it had also formed a partnership with financial services firm NewDay to create a new Argos-branded digital credit offer for the general merchandise business.

Sainsbury’s announced a phased withdrawal from its core banking business in January and in June struck a deal to sell most of its banking operation to NatWest NWG.L.

Last month, Sainsbury's also sold its cash machine operation to NoteMachine.

It expects the combination of commission income from insurance, travel money and ATMs alongside income from the NewDay partnership to deliver sustainable annual income of at least 40 million pounds in the financial year to March 2028.

Sainsbury's also expects Sainsbury's Bank to return to it excess capital of at least 250 million pounds which it plans to return to shareholders.

Shares in Sainsbury's were down 0.8% in early trading Thursday, extending 2024 losses to over 13%.

The group is due to publish first half results on Nov. 7.

($1 = 0.7708 pounds)

(Reporting by James Davey in London and Yadarisa Shabong in Bengaluru; editing by Jason Neely)

((James.Davey@ThomsonReuters.com))