The European Central Bank on Wednesday implicitly took sides with the European Commission in its current run-in with the Bank of Italy over the possibility of foreign banks acquiring Italian rivals.

"We're strongly in favour of an integrated financial market in Europe," ECB President Jean-Claude Trichet told a news conference here.

"I'm sure that the European rule will be respected. This is my own working assumption," Trichet said.

The Frenchman was responding to a question from a journalist regarding the Bank of Italy's reservations about the prospects of Italian banks Antonveneta and BNL being taken over by Dutch bank ABN Amro and Spanish bank BBVA.

Italian central bank chief Antonio Fazio is seeking to protect his country's banking sector from foreign predators, a position that has led to irritation in Brussels.

The Commission addressed a letter to Fazio asking him to clarify measures taken to limit ABN Amro's stake in Antonveneta.