Left-wing Colombian rebels said they have accepted an offer from U.S. lawmakers to witness negotiations to free 61 hostages, including three Americans, that they have held for years in secret jungle camps.

Seven Democratic members of the U.S. House of Representatives wrote a letter to Colombia this month offering to accompany any future negotiations with the Revolutionary Armed Forces of Colombia, or FARC, which has been fighting since the 1960s.

"In terms of a prisoner exchange, progressive people and friends of peace from the United States can contribute to a solution to this part of the Colombian conflict," FARC spokesman Raul Reyes told Noticias Uno television late on Sunday.

The Colombian government, which has also said it would welcome the participation of the U.S. lawmakers, wants to exchange 61 politicians and other high-profile hostages for an unspecified number of rebels in government prisons.

But the two sides have yet to agree on terms for starting talks.
Among the hostages held by the 17,000-member FARC is French-Colombian national Ingrid Betancourt, taken during her 2002 presidential campaign, and U.S. defense contractors Thomas Howes, Keith Stansell and Marc Gonsalves, captured during a drug-eradication mission in 2003.

The FARC wants Colombia to withdraw government troops from a rural area nearly the size of New York City to negotiate the exchange.

President Alvaro Uribe says he is considering the idea but may instead try to rescue the kidnap victims, an option rejected by families of the hostages as too risky.

"We are certainly ready to receive the seven Democratic members of Congress in the demilitarized zone," Reyes said.
The offer to assist in any talks is led by Rep. James McGovern of Massachusetts, who met with families of kidnap victims in Colombia this month.