A "technical glitch" has seen hundreds, perhaps thousands, of NatWest customers charged double for any cash withdrawn from the bank's ATM machines.

NatWest has told us the problem occurred on Monday night and was identified first thing on Tuesday morning, however we have several reports of people being charged double for transactions over the weekend.

NatWest has said it will get back to us on what precisely "technical glitch" means, although we understand it was a software upgrade across the banking system that has caused the problem.

A spokesman told us: "On Monday night, there was a technical glitch that affected a minority of NatWest customers. It was spotted first thing on Tuesday morning. All unnecessary transactions will be refunded by this evening. And of course any account charges in relation to the transactions will be refunded". The last bit meaning if someone is pushed over an overdraft or somesuch.

NatWest said it would get back to us with a figure of the number of people affected although judging by the number of emails we've had, it seems like a significant number. ®