Caixabank was not immediately available to comment.
The offer would come after BPI said on Sunday Angolan investor Isabel dos Santos and Caixabank had failed to reach an agreement on their shareholdings in the Portuguese bank and its costly exposure to the Angolan market.
Caixabank is BPI’s biggest shareholder with a 44 percent stake, while Isabel dos Santos holds 18.6 percent in the Portuguese lender.
Reporting By Jesús Aguado; editing by Julien Toyer
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