Aviva, Britain's second largest insurance group, has received a number of unsolicited approaches from financial and private equity buyers for a U.S. unit estimated to be worth some 1 billion pounds ($1.57 billion), the Sunday Telegraph reported.

The paper said Pat Regan, Chief Financial Officer, has spent a considerable amount of time in Des Moines, Iowa, where the business is headquartered, to prepare the business for sale.

Aviva is seeking to sell or close more than a quarter of its businesses as part of a turnaround drive aimed at regaining the support of investors irked by a flagging share price.

Early in July it sold half its stake in Dutch rival Delta Lloyd for 318 million pounds.

Prudential Plc and Manulife are among four potential buyers bidding for Aviva's Malaysian business in a deal worth about $500 million.

Aviva has not formally appointed an investment bank to run the process of selling Aviva USA but is expected to choose Goldman Sachs, the Sunday Telegraph said.

Aviva did not immediately return calls requesting comment on Sunday.

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