Archbishop Giovanni Lajolo made these statements in London, where he is in contact with Britain's Foreign Secretary Jack Straw.
The request was made as Rome prepares for U.S. President George Bush's tentative June 4 visit to John Paul II in the Vatican. The Holy See has not yet confirmed the visit.
The prelate summarized the Vatican's position on Iraq thus: "To re-establish the internal security of the country, to collaborate with all the forces that are in Iraq to help the people, and to make the latter perceive that they are not there to oppress them but to help them, and to restore independence and sovereignty to the country as soon as possible."
"It is necessary that the U.N. intervene," Archbishop Lajolo explained in statements published today by the Italian newspaper La Repubblica.
"It is not easy," he added, "A sacrifice is being called for, but this generosity of spirit is required. Although the U.N. was excluded at the beginning of the war, it is necessary that the United Nations intervene to put an end to the war."
The Vatican official said that the most urgent priority is "to put as head of the government in Iraq as soon as possible an Iraqi leader, who does not speak to Iraqis in English, but in Arabic, in keeping with their sensibility."
"Moreover, it is necessary to make it understood that work is being done according to a sure calendar, oriented to the full recovery of the country's sovereignty and independence," the archbishop said.
The objective is that foreign troops be able to leave the country "as soon as possible," he added.
Meanwhile, "it cannot be imagined that the United States will not be commanding the military operations, but of course they will have to be in close agreement with the Security Council" of the United Nations, the prelate said.
"Surely they are not there to decide as they wish," he said. "In fact, I think that they do not intend to have a force that acts arbitrarily. I think the United States wants to guarantee the security of the country and to withdraw honorably from Iraq as soon as they can."
The archbishop continued: "Weapons of mass destruction have not been found and the intention to establish a democratic regime is certainly positive, but one must also take into account that democracy needs a cultural background."
"We will have to be content with sufficient forms of democracy, which safeguard the essence but, above all, what is urgent is a regime accepted by the people," he said.
Archbishop Lajolo said that he thinks the American-perpetrated acts of torture against prisoners in Iraq have been "for the United States a more serious blow than September 11 -- with the difference that the blow was not given by the terrorists, but by the Americans themselves."
In the Arab countries, he warned, "the great mass of the people, under the influence of the Arab media, feel a growing animosity and hatred toward the West."
"In fact, the West is often identified with Christianity and it is an identification that is not totally lacking in reasons, as indeed the West has been seasoned by Christian values and many are inspired in those values," the prelate said. "Let's think of the United States, in the motto: 'In God We Trust.'"
In this context, John Paul II's opposition to this war was providential, as it impedes its being perceived as a Christian attack on Islam, Archbishop Lajolo said.
"The Pope spoke very clearly," he added. "If he had been heeded, now they wouldn't have to lament so much. Violence generates violence; war calls up war. I often remember what Lincoln said: 'There is nothing good in war, except the end.'"