Defense Secretary Donald Rumsfeld, saying "momentum is building" for possible war with Iraq, arrived in Europe Friday to press Washington's case for military action.On a three-day trip dominated by the twin threats from Iraq and North Korea , he warned that the international community was putting its credibility at risk if it gave Baghdad more time to comply with U.N. arms inspections.

"This is a critical time," Rumsfeld told reporters on his airplane from Washington.

He insisted "momentum is building" in favor of military action against Iraq while the "center of gravity is shifting in the (NATO) alliance" away from older members France and Germany -- who oppose the U.S. stance toward Iraq -- and toward the new members in eastern Europe, who back Washington.

Rumsfeld arrived in Europe one day after Secretary of State Colin Powell  made an 80-minute presentation to the U.N. Security Council, using U.S. satellite photos and telephone intercepts to make a case for possible war against Iraq.

Rumsfeld will meet Prime Minister Silvio Berlusconi and other officials in Rome Friday to underscore U.S. appreciation of Italy's support for Washington's position.

He will also visit troops at the U.S. Air Force Base in Aviano, Italy, then fly to Munich where he will address a major European security conference and hold talks with the defense ministers of Germany, Russia and other countries.

Despite Powell's presentation, key veto-wielding Security Council members France, Russia and China as well as Germany, which currently holds the presidency of the 15-member council, are resisting military action.

They want U.N. inspectors to have more time to unearth to find out whether Iraq possesses weapons of mass destruction.

"OLD EUROPE"

Rumsfeld will use the Munich meeting to argue that allowing more time for inspections makes sense only if Iraq was cooperating with the United Nations . Washington says Baghdad is doing the opposite.

The defense secretary insisted there would be "no hard sell" directed at France or Germany.

"They are going to make up their own minds and they have. Germany certainly has. I would assume they would stick with it. I just don't know. I don't know what France will do," he said.

President Bush  said Thursday he would support a new U.N. resolution authorizing war against Iraq, saying "the game is over" for Iraqi President Saddam Hussein  and challenging the Security Council to stand up to Iraq's defiance.

Rumsfeld recently angered France and Germany by calling them part of "old Europe" but on his flight to Europe he appeared to downplay tensions, noting NATO has often had disputes in its 50-year history.

He said the number of U.S. troops in Germany could be reduced under a study of U.S. basing needs that has been underway for two years, but gave no hint decisions were close.

Rumsfeld made a point of expressing strong concern that the number of states acquiring nuclear arms may be accelerating and warned that a decades-old system of international treaties may no longer be sufficient to deal with the problem.

He outlined no specific remedy but said addressing the threat will require a serious long-term effort by the international community involving economic, political and, where necessary, military steps.

Rumsfeld cited North Korea, which has threatened to resume nuclear arms production as "the leading example" of the problem. Pyongyang recently announced its withdrawal from the Nuclear Non-Proliferation Treaty, under which it pledged to forsake nuclear weapons.

PHOTO CAPTION

Italy's Prime Minister Silvio Berlusconi (R) and U.S. Defense Secretary Donald Rumsfeld smile during a meeting at the Chigi Palace in Rome, Feb. 7, 2003. Rumsfeld said 'momentum is building' for possible war with Iraq as he arrived in Europe before meeting with top Italian officials. Rumsfeld is to visit troops at the U.S. Air Force Base in Aviano in northern Italy and then fly to Munich, where he will address a major European security conference. (Alessia Pierdomenico/Reuters)