President Bush said Friday that "our country is in more danger of an attack" because of Congress' failure to extend a law that makes it easier for the government to spy on foreign phone calls and e-mails that pass through the United States.

Democrats, in turn, accused Bush of fear-mongering and misrepresenting the facts.

Bush and Vice President Dick Cheney met with Republican congressional leaders in the Oval Office to discuss the impasse with the Democratic-led House. Lawmakers left Thursday for a 12-day recess without acting on the law, which expires at midnight Saturday. The president said Congress should complete work on the bill as soon as possible.

Bush argues that without the extension, the intelligence community will not have the tools necessary for protecting the nation from terrorism. Democrats, equally adamant, say he has the authority he needs to intercept terrorist communications, even if the law expires.

"American citizens must understand, clearly understand that there's still a threat on the homeland. There's still an enemy which would like to do us harm," Bush said. "We've got to give our professionals the tools they need, to be able to figure out what the enemy is up to so we can stop it."

"By blocking this piece of legislation, our country is more in danger of an attack," he said.

House Speaker Nancy Pelosi, in a statement Friday, said Bush was "misrepresenting the facts on our nation's electronic surveillance capabilities." She said his refusal to support a temporary extension of the law "can only mean he knows our intelligence agencies will be able to do all the wiretapping they need to do to protect the nation."

Senate Majority Leader Harry Reid, in a separate statement, said that the expiration of the law does not threaten the safety of Americans. "The president and his allies know this," Reid said. "It is time for them to stop fear-mongering and start being honest with the American people about national security."

Republicans insist there's no time to waste. "The Democratic leaders ought to be held accountable for their inaction," House Republican leader John Boehner told reporters after the White House meeting.

Behind both sides' rhetoric, the issue of what the government can and can't do is complicated by a quirk in the temporary eavesdropping law adopted by Congress last August. It allows the government to initiate wiretaps for up to one year against a wide range of targets. It also explicitly compels telecommunications companies to comply with the orders, and protects them from civil lawsuits that may be filed against them for doing so.

But while the wiretap orders can go on for a year from the time they started, the compliance orders and the liability protections go away when the law expires Saturday night, says Director of National Intelligence Mike McConnell.

"There is no longer a way to compel the private sector to help us," he said Thursday in an Associated Press interview.

Even if the law expires, the government can get an order from the secret Foreign Intelligence Surveillance Court to compel their cooperation. That court was created 30 years ago for just such a purpose. But McConnell rejects that option. He says the process of getting a court order ties intelligence agents up in red tape.

The 1978 Foreign Intelligence Surveillance Act requires court permission to tap wires inside the United States. Changes in technology since then mean much of the world's computer and phone traffic passes through the United States, much of it on fiber-optic cable. Successive court cases say court orders are needed to listen in on any of them, McConnell said.

To get a court order, intelligence agents have to prove they have "probable cause" to believe a target is foreign agent or terrorist before being allowed to tap a line inside the United States, even if the communication originates and ends in a foreign country.

It is difficult for intelligence agents piecing together shreds of information to get enough to merit probable cause, he said. By the time they can amass enough information to do that, the phone number they wanted to track might already be obsolete, McConnell said.

"More than likely we would miss the very information we need to prevent some horrendous act from taking place in the United States," he said.

The FISA law does make provisions for fleeting targets when there is not time to fill out the paperwork. Within a few days, though, the paperwork must be completed and probable cause proved to get an order approved.

The easy solution, say Democratic congressional leaders, is to extend the current law long enough to allow the House and Senate to work out the differences in their respective surveillance bills. The House finished its version in October, but the Senate did not finish until this week, pushing Congress hard up against the deadline.

The law had been set to expire on Feb. 1. The White House reluctantly agreed to a 15-day extension but refuses to approve any more, and has appealed to House leaders to simply approve the version approved by the Senate, which includes the legal immunity for telecom companies the president wants.

The immunity provision protects phone companies that helped the government in its warrantless wiretapping program conducted outside the authority of the FISA court, a feature the House intentionally left out.