MILAN, April 21 (Reuters) - Shareholders in BPER Banca on Wednesday backed the appointment of Piero Montani as the new chief executive of Italy's fifth-biggest bank which is preparing to jostle for a role in the sector's consolidation.

Montani, 67, has a well-established track record in deals and restructuring.

He was picked by BPER's top investor, Unipol, to replace Alessandro Vandelli, who joined BPER in 1984 when he was just 25 and became CEO in 2014.

Vandelli last year oversaw the acquisition of around 600 branches that lifted BPER's assets to around 100 billion euros.

Financial group Unipol, which controls insurer UnipolSAI as well as around 20% of BPER, has been advocating expansion for the bank while eyeing a bigger distribution network for its products.

Unipol last year threw its weight behind the idea of a merger between BPER and Banco BPM to create a third large banking group in Italy.

The arrival of Montani, who has experience in leading phases of transition, has been seen as potentially speeding up a tie-up.

BPER Banca and Banco BPM have been holding talks, people close to the matter have previously said, citing valuations and governance, including Vandelli's role, as hurdles standing in the way of a possible accord.

A source close to the matter last month told Reuters Montani would give new strength to discussions with Banco BPM, making it easier to overcome governance issues.

But Unipol CEO Carlo Cimbri appeared to buy time when he told an Italian daily in March that Montani would need time to study all options while BPER worked on integrating the new branches.

Montani oversaw the merger of Banca Popolare di Novara and Banca Popolare di Verona in 2002. A year later, he became CEO of Antonveneta, which was first bought by Dutch group ABN AMRO and later by Italy's Monte dei Paschi di Siena.

In 2012-2013 he was also CEO of Banca Popolare di Milano which four years later merged with Banco Popolare to form Banco BPM. (Reporting by Andrea Mandalà; editing by Valentina Za, Kirsten Donovan)