In a defiant statement delivered before flying to Berlin, the US Secretary of State responded to European demands for explanations of secret CIA flights from EU territory by insisting that aggressive US actions had “prevented attacks in Europe” and “saved innocent lives”.

Despite the uproar in Europe over America’s “extraordinary rendition” of suspects to countries such as Afghanistan, and claims that secret CIA prisons are located in Romania and Poland, Dr Rice said that she expected American allies to co-operate and keep quiet about sensitive anti-terrorism operations.

Abandoning the emollient tone that she has adopted towards Europe during her 11 months in office, she pointedly reminded European governments that they had helped the US for years in a “lawful” policy of rendition — the removal of suspects to third countries for interrogation.

Dr Rice said: “It is up to those governments and their citizens to decide if they wish to work with us to prevent terrorist attacks against their own or other countries and decide how much information they can make public. They have a sovereign right to make that choice.”

Debate between democracies was healthy, she said, adding: “I hope that debate also includes a healthy regard for the responsibilities of government to protect their citizens.”

Dr Rice said: “We cannot discuss information that would compromise intelligence, law enforcement and military operations. We expect other nations share this view.”

While Dr Rice denied that the CIA used torture, she refused to address the allegations of covert prisons that have caused consternation across Europe and not least in Romania, where she is due today.

She was rewarded with a statement of support from Jack Straw, the Foreign Secretary, who had written to Washington on behalf of the EU demanding an explanation of the CIA’s activities.

“All European countries share the determination expressed by the US to protect our citizens from the threat of terrorism, while operating within international law,” he said.

The new Government of Angela Merkel, the German Chancellor, anxious to repair frayed relations with Washington, was also at pains to play down talk of a new transatlantic rift. But the controversy still threatens to overshadow Dr Rice’s four-day trip to meet Frau Merkel, sign a new defence pact with Romania, support Ukraine’s fledgeling Government and attend Nato meetings in Brussels.

The CIA is alleged to have made hundreds of secret flights over Britain, Germany, the Netherlands, France, Sweden, Denmark and the Irish Republic. The Council of Europe, an intergovernmental human rights group, has begun an investigation. A total of 210 flights are alleged to have been made from British airports. Der Spiegel, the German magazine, has claimed that 437 CIA flights landed in or crossed German airspace.

In her detailed response to the EU request for an explanation, Dr Rice said that the US “will use every lawful weapon to defeat these terrorists”. This included renditions, which, she argued, had been practised for years by the US and other democratic governments.

Stephen Hadley, the US National Security Adviser, said on Sunday that rendition had been used to bring the terrorist known as Carlos the Jackal to justice in France, and to seize the bombers who staged the first attack on the World Trade Centre in 1993. “Renditions take terrorists out of action . . . Such renditions are permissible under international law,” Dr Rice declared.

“The US does not use the airspace or airport of any country for the purpose of transporting a detainee when we believe he or she will be tortured.

“With respect to detainees, the US complies with its laws, its Constitution and its treaty obligations.”

Terrorists were sometimes captured far from their homes and had information that could save thousands of lives. “We must bring terrorists to justice wherever possible.”

She added: “The US has fully respected the sovereignty of other countries that have cooperated in these matters. The US is a country of laws. The US must protect its citizens.”

But by suggesting that whatever the US has done has had the co-operation of its European allies, Dr Rice risked piling extra pressure on governments to explain whether they had violated international laws.

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