MILAN (Reuters) -Italian regional lender Banca Popolare di Sondrio said it had postponed the approval of a new business plan due to uncertainties stemming from the Ukraine crisis, the potential indirect impact of which it was analysing. The bank, widely known as Pop Sondrio and based in the mountains north-east of Milan, has minimal direct exposure to Russian and Ukrainian customers, it said in a statement. But it added it was reviewing any potential effect from its exposure to customers operating in sectors hit by the crisis. It is also monitoring on a daily basis its financial risk exposure,…