Another bank scam

Got a call on my mobile today, and the person calling me claims to work for a bank and says he needs to test my account.

He then asks for all my account details, and says he needs to take £35 out of the account to test it. He tells me not to worry as the cash will come back at the end of the month.

It goes without saying I told him to **** off and did not tell him any of the account info.