A number of UK banks have undergone an exercise to demonstrate that they can cope with a cyber attack that prevents customers from accessing cash, and public transport disruptions during the London 2012 Olympic Games.

Some 87 financial firms and banks, including HSBC, Barclays, Royal Bank of Scotland and Lloyds, took part in the exercise yesterday. The aim was to see how quickly the financial sector could restore services to 'business as usual' after major disruption.

The cyber attack scenario involved a range systems going down, including the internet, ATMs, telecoms, and wholesale and retail payment systems.

The banks were measured on how they notified customers of problems with accessing their accounts and money.

In addition, the exercise tested how firms dealt with the systems crashing if their staff could not be contacted, and if they could not get to the office to deal with the cyber attack.

Just a few weeks ago, it took HSBC a number of hours to resolve a mainframe problem that knocked down its online banking systems, which stopped customers from paying for goods and services with their bank cards.

A day after, RBS and Natwest customers experienced problems accessing their bank accounts online following an IT systems upgrade.

The Bank of England and HM Treasury helped design the two 2012 exercises, which banks took part in voluntarily.

The Financial Services Authority (FSA), which ran the tests, said: "There are no passes or fails. The exercise is about firms assessing their business continuity systems and updating them where necessary and the authorities identifying areas for further attention."

The FSA plans to publish the results of the exercise in February.