Interior ministers from Britain, France, Germany, Italy, Spain and Poland also exchanged insights into how best to engage the European Union's Muslim minorities in the fight against terrorism, British officials said.

European Muslims increasingly fear they are unfairly tarred with the brush of terrorism and object to what they see as blatant prejudice over their choice of dress and their strict observance of their religion.

Preventing terrorist attacks in Europe

The two-day conference of the so-called G6, at a neo-Gothic mansion hotel near Stratford-upon-Avon, the birthplace of England's most famous dramatist, William Shakespeare, will also tackle illegal immigration and organized crime.

"What is obvious is that the biggest threat to all European nations, the common threat if you will, is from terrorism," British Home Secretary John Reid said before joining his EU counterparts for two days of talks.

In what he called an "almost unprecedented move," Reid said the head of Britain's domestic spy agency MI5, Eliza Manningham-Buller, would join the informal meetings as part of increased efforts at sharing intelligence.

"We are all absolutely committed to common action -- research into liquid explosives, sharing intelligence," Reid told reporters.

Britain arrested two dozen people -- mainly Britons of south Asian Muslim background -- when it announced in August that it had foiled a plot to blow up US-bound airliners with liquid explosives.

A Home Office spokeswoman said later that the six ministers stressed the need for "closer co-operation to combat and pre-empt terror attacks," including through efforts to identify websites used for terrorism. The six also vowed to improve security of their transport systems, she said.

Both the British capital London and the Spanish capital Madrid suffered massive bombings to their transport systems in the past two years.

Working with Muslim community

Reid said the interior ministers from the biggest European countries would also discuss how to integrate their Muslim communities into mainstream society and isolate the extremists in their midst.

Reid said the message from the talks is: "The enemy is terrorism. The enemy is not Islam and the dividing line is between terrorists and the rest of us and not between two civilizations or between two religions."

Security was tight at the grounds with visitors having to pass through a number of police checkpoints and iron barriers on back roads to the hotel, which is set in 40 acres (16 hectares) of sprawling countryside.

More than 350 police officers were protecting the area, according to Warwickshire police.

The G6 -- launched in 2003 by London and Paris -- has no formal decision-making powers and according to Britain's Home Office aims to "boost activity and co-operation, which can then be taken forward at full EU level".

But despite claims from the group that its meetings are transparent, some European lawmakers have expressed fears it is unaccountable and has too much influence in forging security policy in the 25-member bloc.