WASHINGTON - The White House said Thursday it was considering an executive order on cybersecurity after legislation on infrastructure protection failed again in the Senate.

"The president is determined to protect our nation against cyber threats," said Caitlin Hayden, spokeswoman for the White House National Security Council after Wednesday's failure in the Senate of a bill aimed at protecting U.S. "critical infrastructure" from cyber attacks.

Hayden said the White House was exploring ways "to more effectively secure the nation's critical infrastructure by working collaboratively with the private sector" and that this may result in an executive order.

She said such an order "is not a substitute for new legislation" and "doesn't create new powers or authorities (but) it does set policy under existing law."

In the lame-duck session, the bill backed by President Barack Obama failed to get the 60 votes needed to proceed under Senate rules. It was backed by a 51-47 vote.

The failure of the bill for the second time in three months prompted political sniping from supporters and detractors.

"Once again, Senate Republicans have chosen to filibuster much-needed cybersecurity legislation and, in so doing, have ignored the advice of the country's most senior military and national security officials," said Senator Jay Rockefeller, a key backer of the measure.

"Republican members have once again sided with the Chamber of Commerce, and not our military officials, on a national security issue."

Republican Senator Charles Grassley, however, claimed the bill was "flawed" and failed to see adequate debate.

"No one disputes the need for Congress to address cybersecurity," Grassley said.

"However, members do disagree with the notion this problem requires legislation that increases the size of the federal government bureaucracy and places new burdens and regulation on businesses."

The measure was blocked amid opposition from an unusual coalition of civil libertarians -- who feared it could allow too much government snooping -- and conservatives who said it would create a new bureaucracy.