President Bush said Thursday that while it's been more than six years since the Sept. 11 attacks, the United States must not become complacent about terrorism.

In a speech marking the fifth anniversary of the creation of the Department of Homeland Security, Bush said U.S. officials have helped foil numerous planned attacks, including a plot to fly an airplane into the tallest building on the West Coast and another to blow up trans-Atlantic passenger jets.

"The enemy remains active — deadly in its intent — and in the face of this danger, the United States must never let down its guard," Bush said.

Bush continued to pressure the House to act on Senate-passed legislation needed to renew an intelligence law that governs how the government can eavesdrop on suspected terrorists. The law expired Feb. 16 and the House and Senate have yet to reconcile different versions of a new intelligence bill.

The Senate bill provides retroactive protection from lawsuits for telecommunications companies that wiretapped U.S. phone and computer lines at the government's request, but without the permission of a secret court created 30 years ago to oversee such activities. The House version does not provide such immunity against lawsuits.

"To stop the attacks on America, we need to know who the terrorists are talking to, what they're saying, what they're planning," Bush said. "We cannot get this vital information without the cooperation of private companies.

"Unfortunately, some private companies have been sued for billions of dollars because they are believed to have helped defend America after the attacks of Sept. 11. Allowing these lawsuits to proceed would be unfair, because if any of these companies helped us, they did so after being told by the government that their assistance was legal and that their assistance was necessary to defend the homeland."

House Speaker Nancy Pelosi, D-Calif., had said it would take about 21 days to reconcile the two bills. That time runs out this weekend, Bush said. The House, however, isn't near finishing a compromise version of the law, and there has been no agreement about what to do about the contested provision to give telecommunications companies legal immunity.

Pelosi said Thursday that the House is working to find a compromise bill with the Senate, but offered no timeline.

"At the time, House leaders declared they needed 21 more days to work out their differences and get a bill to my desk," Bush said. "The deadline arrives on Saturday. If House leaders are serious about security, they will need to meet the deadline they set for themselves, pass the bipartisan Senate bill, and get it to my desk this Saturday."