After a thorough overhaul of its log-in procedures, online bank First Direct has seen many of its customers struggling to access their UK current accounts.

Every one of the bank’s 700,000 customers has been told that they must have a new user name and answers to a set of personal questions as First Direct attempts to make its online systems more secure.

The process started last Friday and led to a mass of people trying to access their UK current accounts over the weekend. The site was still out of action for many users on Tuesday.

Spokesperson Amanda Brown said: “The volume of people trying to log on and change their details led to a spike in users which the site struggled to cope with.

“Tuesday’s surge in traffic to the site may have been caused by a lag of people frustrated from over the weekend and trying to recommence their Internet banking activities.

“People trying to contact us via the telephone call centre experienced long waits because of the sheer numbers calling us to say they couldn’t log on.”

She added: “Some customers managed to set up their new details but soon forgot them and locked themselves out of the system. This only added to the pressure on the call centre.”