Families of dozens of hostages held by Colombia's FARC rebel army held an emotional vigil Sunday as anxieties grew over the expected pre-Christmas release of some of the prisoners into Venezuelan hands.

With reports that the release could be put off until the New Year, hundreds of relatives joined the overnight vigil for the hostages.

The family of French-Colombian Ingrid Betancourt sent the kidnapped politician words of encouragement via the local radio station.

"Mom, it is hard, so hard to spend Christmas without you," Melanie Delloye, Betancourt's daughter, said from Paris.

But the daughter said "we must remain strong" and asked that her mother look after herself for the sake of her family.

"I would give my life to be at your side," Yolanda Pulecio, Betancourt's mother, said in the message.

"Look after yourself my love, eat well, take care, and may you come out soon," she told Betancourt, who has been held captive by the Revolutionary Armed Forces of Colombia (FARC) since 2002.

The messages for Betancourt on Sunday came during vigil ceremonies in the Colombian capital attended by hundreds of relatives of 45 hostages held by the Marxist rebels.

The event was broadcast through the early morning hours until dawn Sunday on Radio Caracol, amid expectations of the promised release of three of the hostages.

FARC on Tuesday said it would free Betancourt's aide Clara Rojas, along with her three- or four-year-old son Emmanuel -- who was born in captivity to Rojas and a rebel father -- and lawmaker Consuelo Gonzalez de Perdomo.

Rojas's family told El Tiempo newspaper Sunday that there were toys around a Christmas tree at their home waiting for the little boy's return.

"My sister will be shocked when she sees how her mother has aged two decades in just five years and 10 months," Clara Rojas's brother Ivan told the newspaper.

"Mama is afraid she will die before seeing her daughter again. I don't think that she can wait another Christmas," he said of their mother, who is 77.

After the failure of talks with the government of President Alvaro Uribe to swap the 45 hostages for some 500 FARC members held by the Colombian authorities, the rebels said the three would be released to leftist Venezuelan President Hugo Chavez, though no time frame was given.

Speaking in Cuba late Saturday, Chavez said he would return Sunday to Venezuela to finalize arrangements for the "delicate operation."

But on Saturday Colombian senator Piedad Cordoba, who is working with Chavez on the release, said that ongoing Colombian military operations against FARC could delay the release.

"There are a lot of operations in the country (Colombia), they are not going to suspend them and it could cause a delay," Cordoba said during a short visit to Caracas to meet with diplomats and hostage families.

The delay is likely "until there are conditions that don't work against the security and integrity of the hostages," she said.

Until then, she added, "I don't know the date or hour, nor the place for the handover ... I don't know if it will be here, in Brazil, in Ecuador, or on the border."

On Sunday the Venezuelan newspaper Vea, which is close to the government, also said that the handover "is difficult" and suggested that their release might not come until early January.

Meanwhile on Sunday Brazilian President Luiz Inacio Lula da Silva offered to Uribe the use of Brazilian territory for negotiations for a prisoner swap with FARC.