Sept 15 (Reuters) - Banco BPM CEO Giuseppe Castagna says:
* About to invite bids to sell two portfolios of unsecured loans worth 2 billion euros, there could be 40-50 potential bidders
* Hopes to close sale of the two portfolios by year-end
* Hired Prelios to conduct due diligence on 3-3.2 billion euro portfolio of both secured and unsecured loans to be sold in first few months of 2018
* Expects four binding offers for new bancassurance accord by the end of month, to pick new partner by end-October but will then need regulatory approval Further company coverage: BAMI.MI