With first lady Laura Bush presiding, the American flag was raised today outside the headquarters of the U.N. Educational, Scientific and Cultural Organization in the French capital, signaling the return of the United States to a body it left 19 years ago during the Cold War, citing corruption, mismanagement and an anti-American bias.

In a speech, Bush said that UNESCO "can now help achieve peace by spreading the values that will defeat terror and lead to a better and safer world. . . . As the civilized world stands against terror, UNESCO's work can make an enormous difference."

She also paid a call on President Jacques Chirac at the Elysee Palace. Chirac met her at her car and elaborately kissed her hand in greeting, at a time when the French and U.S. governments remain divided over the future of Iraq.

The U.S. ambassador to France, Howard Leach, called Laura Bush the president's "most important emissary."

Chirac and his visitor did not discuss Iraq, according to a White House official speaking later with reporters. The official described the French president as "gracious" as well as "charming."

President Bush announced the decision to rejoin UNESCO in a speech to the U.N. General Assembly a year ago. At the time, he was seeking allies in his emerging plans for war against Iraq and facing allegations that his administration was intent on a unilateral foreign policy that ignored traditional allies and international treaties.

When President Ronald Reagan withdrew the United States from UNESCO in 1984, the organization had come to symbolize for many U.S. critics their view of a failed United Nations -- overly bureaucratic, costly, wasteful and imbued with an anti-Western, anti-capitalist bias often directed against U.S. foreign policy.

Critics also applauded the decision to withdraw because the organization, through links with the U.N. Population Fund and its non-governmental partner, International Planned Parenthood, supported abortion and other programs the critics considered to be "anti-family" in developing countries. UNESCO had also drawn ire for advocating what it called a "new world information order" to challenge the power of the Western media.

In ordering the turnabout, Bush went against some members of his own party, particularly in the House of Representatives. "This organization has been reformed, and America will participate fully in its mission to advance human rights and tolerance and learning," he said last year in announcing the new policy.

In her speech today, Laura Bush said the United States, which becomes the 190th member, intended to be a "full, active and enthusiastic participant" in the organization that it helped found in 1945. "We have much to offer, and we have much to learn," she said.

The United States officially resumes its membership on Oct. 1.

"This is a good day for UNESCO," said the organization's director general, Koichiro Matsuura. "A new nation is joining forces with us, bringing with it vast intellectual and cultural resources, along with partnership and good will."

The American return will add about $60 million to UNESCO's current annual budget of $544 million. The move is also likely to increase the number of American faces at the organization's headquarters near the Eiffel Tower and Napoleon's tomb; there are currently only 23 Americans working at UNESCO.

When the Bush administration last year announced its decision to return, it was declining to ratify the Kyoto protocol on global warming, was refusing to take part in the International Criminal Court and had withdrawn from an arms control treaty with Russia. Many analysts viewed the intended return to UNESCO as a signal to the United Nations that the White House could act multilaterally as well.

In the United States, the decision was not universally applauded. While the Cold War has ended, rendering moot old U.S. allegations that UNESCO programs often favored the Soviet Union, the anti-UNESCO banner remains in the hands of Americans who object to the organization's information campaign in developing countries, which they say is anti-family and sometimes anti-religious.

"We're hopeful the Bush administration can influence the direction UNESCO takes on many of the issues it deals with," said Douglas Sylva, vice president of the Catholic Family and Human Rights Institute, with offices in New York and Washington.

Sylva said current UNESCO teaching materials, such as radio scripts for public service announcements, "advocate a certain kind of Western sexual permissiveness that is probably the last thing the developing world needs." He said the Bush administration "will probably want to influence teaching materials to emphasize family values and traditional sexual morality."

Laura Bush's remarks at UNESCO came on the first day of a five-day European tour that will also take her to Moscow.

First lady Laura Bush acknowledges applause during her speech at the headquarters of UNESCO in Paris.