'Fortress Berlin' greets Bush

German police have sealed off a 14-block area around the Brandenburg Gate

BERLIN, Germany -- German police have turned the centre of Berlin into a virtual fortress as U.S. President George W. Bush flew in, with the largest security force in post-war history sealing off the government quarter.

About 10,000 police officers completely cordoned off a 14-block area around the Brandenburg Gate for the American leader, whose plane touched down in Berlin at about 8:15 p.m. local time (1915 GMT), for the start of a six-day tour of Europe.

American presidents are often greeted with open arms in the city, where memories linger of the 1948-1949 airlift that kept West Berlin free and President John F. Kennedy's famous "Ich bin ein Berliner" speech after the Berlin Wall was built.

But Bush, the seventh U.S. president to visit Berlin since World War II, will find no such relief on his 20-hour stay that starts a six-day tour of Europe.

Demonstrators who protested on the eve of his visit over a possible U.S. attack on Iraq and Washington's policies on trade, the environment and the Middle East took to take to the streets again for his arrival.

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Police frogmen have been searching the river Spree, sniffer dogs were patrolling the restricted zone, and other police were welding shut sewers and inspecting the insides of lampposts for explosive devices in the unprecedented security operation.

"There will be snipers in place and... we have taken a number of further security steps that are not visible to the public," said police spokesman Carsten Graefe. Some 5,000 police reinforcements have arrived from all over Germany.

German authorities have promised to crack down hard on any violence from anti-Bush protesters.

In all, more than 100 anti-U.S. protests are expected throughout Germany.

In a first demonstration on Tuesday an estimated 20,000 people marched in Berlin's Mitte district to protest against U.S. policies on human rights, the Mideast, the environment and Iraq.

As he left the White House to join his flight to Germany, Bush had a message for European leaders: "Be tough."

Speaking on the White House lawn on Wednesday before boarding a helicopter bound for Andrews Air Force Base to board his plane for the flight to Berlin, Bush said he appreciated the friendship extended by European allies.

"As an alliance, we must continue to fight against global terror," the president said. "We've got to be tough."

He added: "Even though we've had some initial successes, there's still danger for countries which embrace freedom, countries such as ours, or Germany, France, Russia, or Italy."

Bush is planning to use his visit to Germany, Italy and France to rally the coalition and warn against the dangers posed by Iraqi President Saddam Hussein.

The centrepiece of his week-long trip comes on Friday when Bush visits Russia to sign a nuclear arms reduction treaty cutting the deployed strategic nuclear warheads from the world's biggest nuclear powers by two-thirds over the next decade.

In his address to a special session of the Bundestag on Thursday, aides say Bush will declare why he believes the war on terror should be expanded and explain other U.S. policies to a European audience.

Anti-Bush poster. More than 100 separate anti-U.S.protests are planned in Germany

But he faces some opposition in Germany.

Peter Struck, parliamentary floor leader for Chancellor Gerhard Schroeder's Social Democrats, or SPD, said he would admonish Bush about his Iraq policies. Many Europeans fear Bush plans to launch a military action to topple Iraqi President Saddam Hussein.

"As long as it is not certain that Saddam does not belong to the group that provides quarters or support for terrorists such as al Qaeda, there is no reason to take action against Iraq," Struck said.

"It would be completely wrong if the American president would now attempt to do what his father failed to do," Struck said, referring to the Iraqi leader staying in power after the Gulf War under former President George Bush, the father of the current president.

"Naturally I'm going to bring up the subject of Iraq with him Bush," Struck said, adding Schroeder would as well. "The American government has to be criticized where it deserves it."

Antje Vollmer, a parliamentary leader for the Greens party, junior partner to Schroeder's SPD, said Bush was using "an almost missionary approach against evil" which was causing tension and instability worldwide.

Other topics for discussion will include U.S. protectionism over domestic steel, on which the EU, Japan and other countries say they may impose tariffs.