Banco BPM CEO Giuseppe Castagna has raised concerns over potential job losses in the wake of Italian banking group UniCredit's unsolicited takeover bid, reported Bloomberg citing a letter sent to by Banco to its employees.

UniCredit's bid for Banco BPM raises concerns about the potential impact of the deal on jobs, the banking sector's main union said on Thursday. "There is great concern about the employment fallout that could result from the deal.

Banco BPM SpA said the takeover bid it has received from UniCredit SpA wasn’t agreed in advance and isn’t in line with its performance.

Italy's UniCredit on Monday launched a surprise 10 billion euro ($11 billion) bid for domestic peer Banco BPM , which CEO Andrea Orcel said would take precedence over any potential move on Germany's Commerzbank .

Banco BPM SpA, Italy’s third-largest bank, has rejected a €10 billion ($10.5 billion) takeover bid from UniCredit SpA, which aimed to create the country’s largest banking entity. Banco announced Tuesday that UniCredit’s offer undervalued its financial strength and future growth potential,

ROME, NOV 27 - The CEO of Banco BPM, Giuseppe Castagna, wrote a letter to staff Wednesday saying there would be estimated job losses of at least 6,000 if Italy's second-biggest bank UniCredit succeeds in its hostile takeover bid for the country's third-biggest.

Italy reserves the right to use its golden power legislation aimed at shielding strategic assets in regards to UniCredit's plans to take over Banco BPM , Economy Minister Giancarlo Giorgetti said.