The bank, which is now 49 per cent owned by the governments of the Netherlands, Belgium and Luxembourg, announced the sale of the units at the weekend. In late September, Fortis said it was moving to shed part of its ABN Amro holdings. The weekend statement elaborated the details of its sell-off plans.

“The decision taken today in the best interest of our clients and staff is a second step towards a structured solution for Fortis,” Filip Dierckx, chief executive of Fortis, said in a statement.

“The sale will bring an amount of €16.8 billion which will strongly reinforce our financial position and allow us  to further strengthen the balance sheet and liquidity of Fortis,” Mr Dierckx said.

He added: “As a consequence of this transaction, we unfortunately have to say goodbye to our Dutch colleagues of Fortis Bank, of Fortis Verzekeringen and ABN Amro.”

The disposal of the ABN Amro businesses represents a dramatic change of fortunes for Fortis. A year ago, the bank bought the private client businesses of ABN Amro, while two other European banks, UK’s Royal Bank of Scotland and Spain’s Santander, took over the rest of ABN Amro.

In the BNP Paribas deal, the French firm will buy 75 per cent of Fortis Bank Belgium from the government for €8.25 billion in stock and purchase the Belgian insurance operations, Prime Minister Yves Leterme said. BNP Paribas will also acquire 66 per cent of Fortis's bank in Luxembourg.

The Belgian state will have an 11.6 per cent stake in BNP Paribas, and Luxembourg a 1.1 per cent holding, after the purchases aare completed. Belgium will also appoint two new members to BNP's board. Under the terms of the deal with Belgium, Fortis will hive off a €104 billion portfolio of structured products into a separate body. Fortis shares will also be suspended on Euronext stock markets, Belgium's stock market regulator CBFA said. Trading will resume once Fortis investors have been able to examine the impact of the deal between BNP Paribas and the Belgian government, CBFA said.

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