After an intense campaign that deeply divided Croatia, a majority of voters on Sunday voted to ban gay marriage.

According to the AP, more than 65 percent of Croatian voters agreed that “marriage is matrimony between a man and a woman,” while about 34 percent disagreed.

Passage means that Croatia's constitution will be amended to define marriage as solely the union of a man and a woman.

A petition in support of amending the constitution received more than 700,000 signatures and was organized by the Catholic group In the Name of the Family. Catholics were urged to support the measure. Nearly 90 percent of Croatians are Roman Catholics.

Croatia's Cardinal Josip Bozanic told followers: “Marriage is the only union enabling procreation. This is the key difference between a marriage and other unions.”

Croatian President Ivo Josipovic said he voted against the measure.

Josipovic added that while the referendum result must be respected, it would not stop the government from moving forward on a law to allow some rights to gay couples.

“The referendum result must not be the reason for new divisions,” Josipovic said.

Hundreds opposed to the measure rallied Saturday in Zagreb, Croatia's capital. They argued that passage would be a major setback for the country, which joined the EU in July.

Human rights groups opposed to the referendum as an infringement of basic human rights said they planned on filing an appeal with the country's constitutional court.