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Terrorists plotting to carry out a Mumbai-style massacre in western Europe have a list of high-profile targets in their sights ranging from the Eiffel Tower to a hotel near Berlin's famed Brandenburg Gate, according to intelligence relayed to Fox News.

Information about the threat is seeping out as the United States issues a rare blanket travel alert for Americans in Europe, warning about the possibility of an Al Qaeda strike and advising U.S. citizens to be vigilant. The State Department alert did not offer specifics about the targets and countries that could be most at risk, saying only that Americans should be careful around transportation hubs and other popular tourist locations.

But a senior western intelligence official told Fox News on Sunday that a German-Pakistani national interrogated at Bagram Air Base in Afghanistan provided a list of targets. The list was later confirmed by another senior intelligence official.

They include the Eiffel Tower in Paris and the luxury Hotel Adlon near Berlin's Brandenburg Gate. Targets also include the Notre Dame Cathedral in Paris, as well as Berlin's Central Station and its landmark Alexanderplatz TV tower. One official said security has also been tightened around the British royal family.

The State Department alert is one step below a travel warning advising Americans not to visit Europe. It comes after officials warned that Usama bin Laden is trying to execute a multi-city terror attack modeled after the deadly rampage in Mumbai two years ago.

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Undersecretary of Management Patrick Kennedy says they are not telling Americans to cancel their plans to visit Europe.

"We are not, repeat not, advising Americans not to go to Europe," Kennedy said during a conference call.

State Department spokeswoman Nicole Thompson said she could not recall another Europe-wide alert of this nature. She said the department is "arming Americans with information" should they choose to travel and that visitors should use extra caution while traveling around "soft targets" like hotels.

White House spokesman Nick Shapiro said President Obama has been monitoring the threat on a "daily basis" and has pledged to do "everything possible" to disrupt the plot.

A senior administration official said American and European officials are "all in sync" in assessing and trying to stop the threat. The official said the president has met with his security team every day since Friday. The official said newly named Chief of Staff Pete Rouse chaired a conference call with Cabinet secretaries and security officials Saturday evening.

The State Department alert urged U.S. citizens to "take every precaution" and adopt "appropriate safety measures" while traveling.

"Current information suggests that Al Qaeda and affiliated organizations continue to plan terrorist attacks. European governments have taken action to guard against a terrorist attack and some have spoken publicly about the heightened threat conditions," the State Department said.

"Terrorists may elect to use a variety of means and weapons and target both official and private interests. U.S. citizens are reminded of the potential for terrorists to attack public transportation systems and other tourist infrastructure. Terrorists have targeted and attacked subway and rail systems, as well as aviation and maritime services."

If the intelligence is correct, this would be the most involved role that bin Laden has played in plotting attacks since Sept. 11, 2001.

"It's clear and the plot is clear. The clarity of detail on the plans for these attacks is disturbing," one official told Fox News.

There was "some degree of coordination between the multiple teams of attackers targeting at least three Western European cities, but not all know when to hit," the official said, adding the goal was to kill many more than the 173 killed in Mumbai.

Eight Germans and two British brothers are at the heart of the terror plot against European cities, but the plan is still in its early stages, with the suspects calling acquaintances in Europe to plan logistics, a Pakistani intelligence official said Thursday.

One of the Britons died in a recent CIA missile strike, he said. The Pakistani official said the suspects are hiding in North Waziristan, a Pakistani tribal region where militancy is rife and where the U.S. has focused many of its drone-fired missile strikes.

Britain's Foreign Office also upgraded its travel advice for France and Germany, warning Britons going to those countries that the threat of terrorism there is high. Before Sunday's change, the government's travel advice for France and Germany was that the threat from terror attacks there was "general." Germany's Interior Ministry said it saw no need to change its assessment of risks to the country and there were "still no concrete indications of imminent attacks" there. France also has not changed its travel advice.

The U.S. travel alert, which stressed that U.S. officials are working "closely" with the Europeans to track down terror threats, expires Jan. 31, 2011.

The alert urges Americans to register their travel plans online with the consular section of the U.S. Embassy at the State Department website. Travelers can also get updates on security conditions by calling 1-888-407-4747.

Fox News' Jennifer Griffin and Mike Emanuel and The Associated Press contributed to this report.