CAIRO, Egypt – With the president and Congress banging heads over the safety of American ports, opponents of the United Arab Emirates deal will soon discover that America and the UAE are far closer than ever was suspected.

For at least a decade, intelligence officials in Dubai have quietly shared detailed banking records of suspected terrorists, and even neighboring officials in Iran, with American intelligence agencies.

The financial intelligence from Dubai, a principality known as the Switzerland of the Middle East for its closed banking system, has been particularly useful in tracking down much of the money to Saudi charities that have been in league with Al Qaeda, former CIA officials said.

Despite the long-standing security ties between the Emirate and Washington, the Port Authority of New York and New Jersey yesterday decided to file a legal action in a New Jersey federal court to have the deal stopped without delay.

An authority member close to the decision, who asked to remain anonymous, said yesterday that he thought it would transpire that the Dubai Ports World deal did not pose a risk to port security. There is, however, a problem about the public’s perception of the risks attached to the deal, he said.

“The president is on track,” he said. “From first blush it looks like we could be secure, but the public perception is very different. When someone from another country is about to control our ports, we obviously have to look at it very carefully.”

Nonetheless, the four-man security committee of the Port Authority will meet today at 10 a.m. to be briefed by the head of ports police and the head of security on the risks involved if the ports of the two states are to be administered by the Dubai company.

Last night, documents relating to the Treasury Department’s decision to allow the deal showed that the Bush administration attached strict conditions for the sale, requiring the Dubai company to cooperate with future American investigations and disclose internal operations records on demand.

The president this week threatened to cast the only veto of his presidency if Congress follows through on its threat to overturn a decision to allow a British company to sell the ports contract to DP World. Congressional leaders have countered that the Emirates have been a source of funding for Al Qaeda in the past and that one of the September 11 hijackers was a UAE citizen.

The Senate Armed Services Committee will meet today for a briefing from officials representing the departments and agencies of the federal board that approved the sale. But former senior intelligence officials said the UAE has been a strong ally in counterterrorism since long before September 11.

“They could not be more cooperative in terms of knowing who is in their country and what is going on there,” a former CIA operations officer in the Middle East, Robert Baer, said yesterday.

Mr. Baer, whose life story was the inspiration for the Hollywood movie, “Syriana,” called the UAE’s historic cooperation “unprecedented for the region.” “They reported to us that one of the hijackers was coming through the country. They have provided travel documentation, kept track of Iranians, and did the best they could in Saudi Arabia.”

Mr. Baer also said that after September 11, after Mr. Baer retired from the agency, the security services for the Emirates were instrumental in shutting down money transfer operations known as Hawalas preferred by Islamists because of Islam’s prohibition on charging and collecting interest. Mr. Baer said the Emirates were the first country to promise not to allow the Hawala money to be transferred to accounts in America. “They were instrumental in helping us track the money from Saudi Arabia connected to 9/11,” he added.

A former colleague of Mr. Baer at the CIA, David Manners, concurred yesterday. “For as long as I’ve been involved in Middle Eastern affairs, the word around the agency was that these guys were pretty helpful.” He added, “They have been helpful on the banking front, very cooperative.”

One measure of how valuable the relationship with Dubai has been is its impact on America’s Iran policy. In 2003, the White House rejected a plan to publish the financial records of Iranian regime leaders in part because of the diplomatic and intelligence repercussions with Dubai, according to one current and one former administration official. This was part of Iran policy recommendations drafted by the Pentagon in an effort to destabilize Tehran and assist the country’s internal opposition.

The Emirates have also cooperated with America in other facets of the war on terror. In November 2002 authorities there apprehended the man known as Al Qaeda’s admiral, Abd al-Rahim al-Nashiri. According to the 9/11 Commission, Mr. Nashiri attempted the attack on the USS Sullivans in January 2000 and later that year in October the attack on the USS Cole off the port of Aden.

At the same time the 9/11 Commission recalls an incident on February 12, 1999 when CIA officers in Afghanistan spotted who they thought was an Emirate prince with Osama bin Laden at an armed camp considered at the time for a possible military strike. The former National Security Council chief for counterterrorism, Richard Clarke, later that month placed a call to a senior UAE official inquiring about the liaison. The armed camp was closed down soon after Mr. Clarke inquired about the prince.

One former Bush administration familiar with nonproliferation issues conceded yesterday that UAE in the past has provided access and banking intelligence to America. But this former official was also wary of the cooperation. “Do they let us sneak and peek? Yes. But when its certain Saudis funding terrorists or Iranians we might be interested in the answer is no. They let us look at people who they perceive as a threat to them.”

The former official also said that the UAE was not as helpful as it should have been on the proliferation security initiative, a program designed to interdict ships, planes and trucks carrying weapons of mass destruction to rogue states. As a neighbor and banker to Iran, Dubai is of critical importance to stopping nuclear proliferation in Iran.

The freedom chair at the American Enterprise Institute, Michael Ledeen, yesterday said he too was concerned that the deal with Dubai Ports World could end up inadvertently giving the Iranians operational details about American port security. “Dubai cannot totally resist demands from Iran and they cannot totally resist demands from us. So they give us information about Iran, but they give Iran information about us.”