AP 06/17 11:07 EDT V0609 1994 The Associated Press

VATICAN CITY (AP) -- A campaign to curb the world population is pitting Pope John Paul II against the United Nations.

In one of the biggest battles of his 16-year papacy, John Paul has marshaled his cardinals and lobbied world leaders, determined to stop a proposed U.N. program to curb world population growth.

The Vatican says the program, to be adopted at a conference in Cairo, Egypt, in September, will spur abortion and birth control and threaten the traditional Roman Catholic family.

The pope is a resolute opponent of abortion as well as artificial birth control and has shown increasing unease over lifestyles outside the traditional family, assailing proposals to allow homosexuals to marry and adopt children.

His campaign has been building for months, putting him on a collision course with the White House and with liberal Roman Catholic and feminist groups.

At the last population conference, in 1984 in Mexico City, Vatican officials worked with the Reagan administration in reaching a consensus that abortion in no way be promoted.

So when the draft document for the Cairo conference failed to rule out abortion, the Vatican took the unusual step of releasing a message from the pope upbraiding the secretary-general of the conference, Nafia Sadik.

But the Clinton administration is committed to reversing that policy. Clinton came away from talks with the pope at the Vatican on June 2 admitting "genuine disagreements" existed that probably can't be bridged.

Clinton said he's against abortion as a means of birth control but that women should be allowed access to safe abortions.

"These men meeting in Rome are out of step with their church, with women and with governments the world over," said Frances Kissling, president of the Washington-based Catholics for a Free Choice.

The Vatican is not standing still, counting on support from Roman Catholic countries in Latin America and perhaps others in the Islamic world.

This past week, a special meeting of 114 cardinals gave unanimous support to a resolution that, despite population trends shown by various experts, the issue "cannot be legitimately resolved by the introduction or imposition of artificial, unnatural or immoral means."

It took the view that education and development are more effective responses to any potential population explosion "than are coercion and artificial forms of population control."

Significantly, the resolution was put forth by an American cardinal, Archbishop John J. O'Connor of New York, representing a country whose liberal lifestyles trouble the pope.

Just days before, a papal advisory body, the Pontifical Academy of Sciences, warned that unchecked population growth could burden the world with "unsolvable" problems.

But the Vatican's radio network quickly moved to douse any speculation that the report suggested the pope was preparing to modify his position.

"Instead of seeing contradictions and a change of mind on the part of the Holy See on the delicate problems of demographic development, one at least should note that in the positions of the Holy See and the pope himself ... there isn't any lack of awareness of the data about the problem," Vatican Radio said in a commentary.

The pope's views on abortion and contraception are well known, and while the Vatican intends to continue lobbying against them it is also zeroing in on language it sees as playing down the importance of the traditional family in today's society.

To some groups, the pope's resolute stance is only further evidence of a growing distance between the Vatican and lay Catholics, particularly in the United States and Western Europe.

In one of his earlier battles, the pope suffered a stinging defeat when voters in overwhelmingly Catholic Italy upheld the country's liberal abortion law in a 1981 referendum.