US president Barack Obama has ordered an immediate 60-day review of the online security of government IT systems to check for vulnerabilities.

The review will be led by Melissa Hathaway, who has served as cyber co-ordination executive to the US Office of the Director of National Intelligence. Hathaway will also serve as acting senior director for cyberspace for the National Security and Homeland Security councils during the review period.

"The national security and economic health of the US depend on the security, stability and integrity of our nation's cyber space, both in the public and private sectors," said John Brennan, assistant to the president for counter-terrorism and homeland security.

"The president is confident that we can protect our nation's critical cyber infrastructure while at the same time adhering to the rule of law and safeguarding privacy rights and civil liberties."

Hathaway, a former consultant at Booz Allen Hamilton, has been charged in the past with setting up online security systems for US intelligence agencies, and is seen as a wise choice to set high standards.

Private companies are already gearing up to tender for contracts to secure the national online infrastructure, and billions of dollars are expected to be up for grabs.

Rick Howard, director of intelligence at managed security services firm iDefense, welcomed the move by Obama.

"Cyber warfare is now a real threat," he added. "Russian hackers, individually and grouped into cartels, are good at attacking an opposing government’s infrastructure in campaigns of annoyance and frustration."