President Barack Obama warned of cyber threats to critical US infrastructure and called on Congress to take action in an op-ed published Friday in the Wall Street Journal.
"The cyber threat to our nation is one of the most serious economic and national security challenges we face," Obama wrote.
"Foreign governments, criminal syndicates and lone individuals are probing our financial, energy and public safety systems every day."
He cited an incident last year in which a hacker posted pictures of the internal controls of a Texas water plant, and said companies operating natural gas pipelines had also been targeted.
Obama said there had also been increasing attacks on computer systems in the nuclear and chemical industries, raising the prospect of foes targeting critical US infrastructure during war.
"In a future conflict, an adversary unable to match our military supremacy on the battlefield might seek to exploit our computer vulnerabilities here at home," Obama wrote.
"Taking down vital banking systems could trigger a financial crisis. The lack of clean water or functioning hospitals could spark a public health emergency. And as we've seen in past blackouts, the loss of electricity can bring businesses, cities and entire regions to a standstill."
Obama called on Congress to pass legislation to curtail such threats, saying "it would be the height of irresponsibility to leave a digital backdoor wide open to our cyber adversaries."
"For the sake of our national and economic security, I urge the Senate to pass the Cybersecurity Act of 2012 and Congress to send me comprehensive legislation so I can sign it into law."