"All measures have been taken for this summit, there is no reason to worry regarding security," Interior Minister Abdulkadir Aksu told reporters Friday ahead of talks with Deputy Prime Minister Abdullah Gul as well as with army and intelligence officials to discuss security arrangements.

Fears of attacks in Istanbul, Turkey's largest city, have grown since four suicide attacks, blamed on local extremists linked to the Al-Qaeda network, claimed some 60 lives and caused massive destruction in the city in November.

Last month, police arrested six people, thought to belong to the northern Iraq-based radical group Ansar al-Islam, an alleged Al-Qaeda ally, on suspicion of plotting to attack the NATO summit.

Air traffic over the venue of the June 28-29 meeting and its vicinity will be banned and maritime traffic restricted on the Bosphorus Strait, which bisects Istanbul, as part of measures to ensure the safety of an estimated 7,000 guests.

Steel and concrete barriers will be erected around an area with a diameter of 10 kilometers (six miles) to seal off the congress hall where the meetings will take place, the press center and the hotels where the guests will stay.

All traffic into the so-called "NATO valley" will be banned and only those producing specially issued badges will be allowed access.

Besides Bush, US Secretary of State Colin Powell, Secretary of Defense Donald Rumsfeld and national security adviser Condoleezza Rice are expected to attend the summit.

Organizers also expect some 3,000 delegates from 26 NATO member nations and 20 partner countries as well as about 3,500 journalists to attend the Istanbul summit.

WAR.WIRE