Berlin ? Secretary of State Condoleezza Rice aggressively defended U.S. tactics against terrorism on Monday as tough but legal, and countered European complaints over reports of secret CIA-run prisons there by saying America’s efforts with its allies have been “a two-way street” that have saved European and American lives.

Commencing a five-day visit to a Europe that has seethed with resentment over the reports of U.S. prisons and detainee mistreatment, Rice delivered the Bush administration’s most forceful response to a month of growing trans-Atlantic acrimony.

She also went further than others in the Bush administration to insist that Americans do not practice torture or lesser forms of cruel treatment.

“Our people, wherever they are, are operating under U.S. law and U.S. international obligations,” Rice said. She said that includes the U.N. Convention Against Torture, a document the administration has previously said does not fully apply to Americans overseas.

“Some governments choose to cooperate with the United States” in intelligence and other arenas, Rice said before she left for Europe. “That cooperation is a two-way street. We share intelligence that has helped protect European countries from attack, saving European lives.”

Her comments seemed to imply that if any European governments provided secret prisons, they did so willingly.

Rice did not elaborate on how lives were saved. But White House spokesman Scott McClellan referred reporters to an Oct. 6 statement by President Bush that the United States and its allies had foiled 10 serious plots by the al-Qaida terror network in the past four years.

At the time, the White House said those counted several attempted strikes in Europe, including plans to bomb sites in Britain in mid-2004, attack London’s Heathrow Airport using hijacked commercial airliners in 2003 and carry out a large-scale bombing in Britain in spring 2004.

Throughout Monday, Rice refused any outright answer to the underlying question European governments have asked: Did the United States run clandestine detention sites on the continent?

“Were I to confirm or deny, say yes or say no, then I would be compromising intelligence information, and I’m not going to do that,” she said on her plane to Germany.

The European Union has asked for an explanation of U.S. actions, as have individual European allies concerned that their airports, territory or air space may have been used for detention or transport of suspects under conditions illegal in Europe.

The continent’s top human rights watchdog is investigating.