Intelligence and security officials opposed to the deal with Dubai Ports World said ports are vulnerable to the entry of terrorists or illicit weapons because of the large number of containers that enter U.S. territory, regardless of who manages them.

A Persian Gulf state such as the United Arab Emirates could provide an infrastructure for terrorists to penetrate U.S. security as part of a major terrorist operation, the officials said.

One long-term worry is that al Qaeda terrorists will attempt to smuggle a nuclear device into the United States through a port via a shipping container.

Allowing a Middle Eastern company to manage key ports "would be like putting the fox in charge of the henhouse," said one security official, who, like most other critics, spoke on the condition of anonymity.

Another official said the problem is not the company but its location in a region rife with Islamic terrorism.

"You have to be concerned about a firm from that part of the world managing the ports," this official said. "They are more vulnerable to compromise and penetration by terrorists, even if they are just managing the port."

Company officials would be briefed on security procedures and countermeasures that, if compromised, could allow foreign terrorists to get through various screening procedures, the official said.

The Coast Guard is responsible for port security, tracking ships, crews and cargo and search vessels based on intelligence. There is no cohesive hiring or screening process for port workers, however.

Critics said the port deal reflects the Bush administration's pro-business policy bias. The Treasury Department's point man on the issue, Deputy Treasury Secretary Robert Kimmitt, was described by officials as a liberal Republican who in the past clashed with conservative national-security officials during interagency policy disputes.

The United States has 95,000 miles of open shoreline with 361 ports. Annually, about 7,500 ships make about 51,000 port calls and unload more than 6 million shipping containers.

Other senior officials, however, reject politically charged claims that the Dubai Ports World purchase of contracts to run ports in New York, Philadelphia, Baltimore, New Orleans, Miami and Newark, N.J., poses a national security risk. At the White House, National Security Council spokesman Frederick Jones said there are no national security concerns over the Dubai Ports World deal.

"This transaction has been incorrectly reported as being about port security or port ownership," Mr. Jones said. "No. It is about managing port operations. Port security remains the shared responsibility of local port authorities, the Department of Homeland Security, the Transportation Department, the Coast Guard and others."

The port deal was approved by the Treasury-led Committee on Foreign Investment in the United States (CFIUS), in part based on the United Arab Emirates' support for U.S. government activities in the war on terrorism.

U.S. intelligence agencies raised "a couple" of national-security issues that were resolved after talks with Dubai Ports World officials, said Treasury spokesman Tony Fratto. The company, he said, provided "verifiable assurances" that the problems would be resolved, but did not elaborate.

The contract to manage the ports is not expected to involve large numbers of United Arab Emirates or foreign dock workers, but will involve some United Arab Emirates nationals who are Dubai Ports World managers to direct and oversee port operations.

The Department of Homeland Security was the lead agency in supporting the deal, based on past United Arab Emirates cooperation with a U.S.-led shipping container security initiative in Dubai.

The CIA operates a base in Dubai, and U.S. military unmanned aerial vehicles also fly out of the Persian Gulf state for intelligence-gathering missions.

"It's a country that's been involved in the global war on terror with us; it's a country that we have facilities that we use," Defense Secretary Donald H. Rumsfeld told reporters yesterday.

Gen. Peter Pace, chairman of the Joint Chiefs of Staff, also said the U.S. military has close ties to the United Arab Emirates.

"In everything that we have asked and work with them on, they have proven to be very, very solid partners," Gen. Pace said.

Mr. Rumsfeld said both he and Gen. Pace were unaware of the port-deal security issue until the weekend.

The defense secretary said he was reluctant to judge whether the management contracts posed national-security risks because he was not fully informed.