The American banking system needs to prepare for further cyber attacks in the coming months, a leading financial stability group has warned.

The Financial Stability Oversight Council - set up in the wake of the recent economic crisis - said in its annual report that banks needed to plan effectively and communicate with government and other sectors to fend off such incidents.

"Technological failures, natural disasters, and cyber attacks can emanate from anywhere, at any time," the FSOC wrote, according to a report by Reuters. "Preparation and planning to address these potential situations are essential to maintain the strength and resilience of our financial system."

"Security threats in cyberspace are not bound by national borders and can range widely from low to high security risks.”

Earlier this year, a series of sustained DDoS attacks saw the websites of 15 major American banks unavailable for a total of 249 hours over a period of six weeks, according to a report by NBC. A We Live Security report on the attacks can be found here. Referring to these attacks, the FCOS report said, "the knowledge and skill of the attackers appeared to increase over time."

The FSOC said that increased communication was key to protecting the financial system from such attacks. "Public-private partnership improvements in the analysis and dissemination of robust information to improve real-time responses to cyber attacks will enhance incident management, mitigation, and recovery efforts.”

The report also recommended improving communications with other sectors such as energy, power and telecoms.