Telstra has admitted its internal controls were not strong enough to prevent last week’s nationwide network outage.

The telecommunications giant says the disruption was caused by a planned network change that triggered an unexpected system failure.

Consequently, Millions of customers across Australia were affected, with mobile, internet and business services disrupted.

Telstra says the incident exposed weaknesses in its operational safeguards and risk management processes.

However, the company has apologized to customers and pledged to strengthen its network controls to prevent similar outages.

An independent review is now underway to examine what went wrong and recommend improvements at the same time.

The Telstra company also says, rebuilding customer trust remains a top priority following the widespread disruption.