Hortensia Damiana Moran, 40, a religious activist who worked on President Fernando Lugo's election campaign, went public with her allegation a year ago, but at the time said she would not file a formal claim on behalf of her 2-year-old son, Juan Pablo.

But late Wednesday, Moran filed a petition asking a judge to order a DNA test to prove Lugo is Juan Pablo's father, said her lawyer, Rodrigo Aguilar.

Judge Sandra Sanchez confirmed in a statement Thursday that she agreed to accept the claim and that Lugo must respond to it within five days.

Neither Lugo nor his lawyer, Marco Farina, commented immediately.

It was not clear why Moran changed her mind. Her attorney said he would not issue a statement until Lugo responded.

The first woman to sue Lugo for paternity was Viviana Carrillo, 26. Subsequent DNA tests confirmed Lugo is the father of her son, Guillermo Armindo.

The second case, filed by Benigna Leguizamon, also 26, is still pending in an appeals court because Lugo refused to travel to Leguizamon's town to give a DNA sample, instead insisting on sending it from his home.

Leguizamon maintains her 7-year-old son, Lucas Fernando, was conceived during a brief love affair with Lugo that happened when she was working as a cleaning lady at the diocese where he was bishop.

Asked whether the latest claim would tarnish the president's image, Interior Minister Rafael Filizzola replied, "We must not mix personal affairs with government business."

"We have hired a lawyer to deal with this type of issue and avoid getting the government involved," he added.

Lugo has remained single since Pope Benedict XVI excused him from his vows of chastity, poverty and obedience in 2008. On Aug. 16, Day of the Child in Paraguay, he invited Guillermo Armindo, the boy confirmed as his son, to spend the day with him in his home.