A worker's union called the attention of the Commonwealth Bank of Australia (CBA) on its controversial social networking policy, in which employees could be terminated if their Facebook accounts carry unsavoury remarks about their employer.

Never if mind the words directed at criticising CBA came from a friend, the policy allegedly stays, according to the Finance Sector Union, which on Tuesday sent an open letter to the bank urging the company to revisit and reconsider the fairness of the rule.

FSU spokesman Rod Masson said that not only is the policy unreasonable but it also violates the Fair Work Act by sifting through even the most mundane cares of employees who only happen to have engaged in a light banter with a friend listed on his or her Facebook account.

The FSU letter argued that even the most innocent exchanges "about the colour of the tea cups at the workplace, who is winning the footy tipping competition, or what day of the week CBA employees are permitted to wear casual clothes are examples of conversations that would constitute a breach of the policy as it is currently worded."

Masson said that the CBA policy prohibits its employees from commenting or discussing bank-related matters on social networking sites, and more so to air any negative remarks about the company, which includes directives for staff to be vigilant on allowing negative comments on their pages and deleting them when posted by someone else.

The policy as a whole violates employees' freedom to associate, according to Masson, and the threat of firing, he stressed, is also imminent even for employees whose Facebook wall contains negative remarks about the bank, even if the comments came from a friend.

In reaction to the FSU letter, CBA said in a statement that it is now considering some adjustments on the policy, which is a departure from its earlier stance of standing by the existing guidelines for its employees.

CBA said that it is willing to "amend the policy, where it is considered reasonable to do so, to ensure that all of their staff continue to be treated fairly."