The U.N. agency that oversees aviation is pushing new guidelines for cargo security to counter al-Qaida's new mail-bomb strategy, but is stopping short of calling for 100 percent screening of packages, as pilots and some U.S. lawmakers have urged.

The proposed changes by the International Civil Aviation Organization concentrate on "supply-chain security," or checking outbound shipments before they even reach the airport. A draft of new guidelines will go out to all 190 member countries in the next few weeks, the agency says.

Governments are increasingly worried about cargo security as the holiday season swells the number of packages moving around the world.

In October, militants based in Yemen tried to blow up cargo jets with 38 bombs hidden in printer cartridges. The bombs were stopped only because of a tip from Saudi intelligence officials, Transportation Security Administration chief John Pistole told Congress.

Since August, the United States has been screening all cargo loaded onto passenger planes that take off from U.S. airports. But there is no such requirement for cargo-only planes, or for flights coming from abroad.

Last week, a magazine published by al-Qaida urged members to launch more mail bomb attacks, calling them a "good bargain."

"An attack is an attack, whether it's large or small, and we're trying to defeat all of those," said Jim Marriott, head of ICAO's security branch.

The Montreal-based ICAO writes the standards that allow planes to fly easily from one country to another, from the frequencies used by navigation systems to the phrasing pilots use on the radio.

While not binding, the agency's recommendations carry tremendous weight, and member countries usually incorporate them into their aviation laws.

A panel of two dozen ICAO experts had been working on the cargo security measures for several years, and they were approved by the organization's governing council Nov. 17, Marriott said.

The text is not public until member governments submit their comments, but most of the changes focus on inspecting cargo before it leaves for the airport, then protecting it from tampering until it reaches the plane, Marriott said.

The amendment also urges countries to introduce inspection machinery, an important change in poor countries where airports still rely on searches by hand and see little reason to introduce high-tech sensors, he said.

Other parts of the amendment urge countries to secure air-traffic control sites and protect their computers against viruses and digital attacks.

ICAO is preparing to send a draft to member countries for their comments in the next few weeks; the final guidelines will be incorporated into the 1944 Chicago Treaty on international aviation sometime next year, he said.

The U.S. Transportation Security Administration praised the proposal, saying it "exemplifies global collaboration."

"Due to the evolving nature of the threat, this is an ongoing effort for the entire international community," the agency said in a written statement.

However, the ICAO amendment does not set a target for how much cargo must be inspected before being loaded on planes, Marriott said.

That has been a matter of furious debate within the aviation industry, with pilots calling for 100 percent screening of cargo on all planes and shipping companies saying it would cause massive backups.

"Cargo security is the biggest hole in the net," said Gideon Ewers, a spokesman for the Chertsey, Britain-based International Federation of Airline Pilots' Associations. "All cargo aircraft should be treated exactly the same as a passenger aircraft, because they will cause exactly the same amount of damage if they come down."

Rep. Edward Markey, D-Mass., introduced a bill this month that would require screening of all cargo on all commercial planes in the United States, regardless of whether they carry passengers. Markey wrote the original 2007 law regarding passenger planes that took effect in August.

Cargo companies, meanwhile, say inspectors' time would be better spent using intelligence information and computerized criteria to identify suspicious packages. Inspecting every package is impossible, they say.

"You're going to create bottlenecks, slow down commerce and you might even put lives in peril because a lot of cargo that the industry moves is life-saving drugs, biomedical, pharma, that kind of stuff," said Brandon Fried, executive director of the Washington-based Airforwarders Association. He estimated that 100 percent inspection would cost companies hundreds of millions of dollars.

Meanwhile, the European Union is set to unveil its own package of recommendations to impove air cargo security.

On Monday, European Commission Vice President Siim Kallas said the package would include more stringent rules on air freight screening, new criteria for identifying potentially risky cargos, and better intelligence sharing regarding possible threats both within Europe and outside the 28-nation bloc.

Kallas warned that the EU should not fall into the trap of overreacting with new across-the-board screening and control procedures.

"That would paralyze both the aviation industry and our economies, which rely on fast and reliable air cargo services," he said. "That would be a victory for our opponents, who would probably still find another loophole somewhere."

On Wednesday, Germany revoked the licenses of three companies for failing to meet cargo security standards and issued warnings to 20 others. It did not identify the companies or say whether they were shipping firms or manufacturers sending exports abroad.

ICAO has also been moving to tighten international laws against terrorist attacks on planes. In September, it approved two treaties criminalizing attacks on aviation-related computers and the transport of weapons of mass destruction.

Other changes anticipate exotic new ways of hijacking planes, said Denys Wibaux, director of the agency's legal division. One measure makes it a crime to take control of a plane by remote control or to use hostages on the ground to force pilots in the air to obey terrorists' orders.

"It's a remote scenario, but it's the kind of thing we want to make absolutely sure is covered in the international laws," Wibaux said. "Sometimes the reality is even worse than our imagination."

Those two treaties must now be ratified by member countries, a process that could take months or years, he said.


Slobodan Lekic contributed to this report from Brussels, Belgium.