Greece's big banks have seen combined daily deposit outflows of between 500-800 million euros over the past few days, with the pace picking up as the June 17 election approaches, two senior bankers said on Wednesday. Deposit outflows at smaller and medium sized banks were running at 10-30 million euros. With fears growing that Greece may be forced out of the euro, the pace of withdrawals had increased and was especially pronounced on Tuesday, one banker said.