With the Summer Games (search) just a week away, Greek officials said Friday they had overcome snags in implementing the most elaborate security plan in Olympic history.

The first of three NATO (search) surveillance planes arrived at a northern air base and will start patrols Tuesday, officials said.

Athens had faced delays in installing a massive U.S.-built surveillance system and coordinating health responses to a variety of potential terrorist threats. Some of those delays were blamed on construction setbacks at Olympic venues.

"Everything is going according to plan," Public Order Minister Giorgos Voulgarakis said after a two-hour Olympic security meeting attended by 10 ministers, Athens' mayor, police chiefs and top games organizers.

"In terms of security we have done whatever is humanly possible to have secure and very good games in Greece."

Voulgarakis did not elaborate on which difficulties were addressed.

Greece is spending a record $1.5 billion on security for the first summer Olympics held since the Sept. 11 (search) attacks. About 70,000 police and soldiers will be involved in protecting the games.

"We have solved very many problems with the good cooperation between all the agencies involved," government spokesman Theodoros Roussopoulos said.

The security measures include a $312 million communication and surveillance system developed by a consortium led by San Diego-based Science Applications International Corp., or SAIC. The system will be the nerve center for authorities, linking police, armed forces and other services.

It includes a 200-foot blimp mounted with high-resolution cameras and chemical agent "sniffers." The system was implemented nearly two months behind schedule.

NATO will help with surveillance planes, sea patrols and emergency response forces. The first of three NATO Airborne Warning and Control System, or AWACS, planes arrived Friday at the Aktio air base in northern Greece, defense officials said.

The AWACS will Greek radar and fighter plane patrols.

NATO also is deploying 200 soldiers to respond to a potential chemical or biological attack and is assigning its entire Mediterranean naval fleet to patrol Greece's outer boundaries. A 400-strong rapid reaction force, to be led by U.S. personnel, will be based in Germany and Italy.

Also Friday, Merchant Marine Minister Manolis Kefaloyiannis reviewed the security measures at Athens' main port of Piraeus, where eight cruise ships, including the world's largest passenger ship — Queen Mary 2 — will dock as floating hotels.

"The security measures are ready," Kefaloyiannis said after walking through a metal detector.

The cruise ships — which will house heads of state and senior Olympic officials — will be protected by several thousand elite commandos and other soldiers, barbed-wire fences fitted with motion sensors, surveillance cameras, X-ray machines and detectors for radiological, chemical and biological materials.

Gunboats and helicopters also will patrol constantly.