A French mission to treat an ailing French-Colombian senator held hostage in the jungle by Farc guerrillas was in jeopardy after her captors ruled out any unilateral prisoner release.

A French aircraft was on standby yesterday at Catam military airport in Bogotá waiting to carry a medical team to treat Ingrid Betancourt, 46, should her captors allow it. Ms Betancourt, a former Colombian presidential candidate, who also has French citizenship, has been held by Farc for six years — one of hundreds of hostages — as the group tries to negotiate the release of its members from jails in Colombia and the US.

Hugo Chávez, the Venezuela President — who secured the unilateral release of six Farc hostages earlier this year — has said he is ready to help the French mission. He urged Nicolas Sarkozy, the French President, to try to persuade President Bush to add his weight to efforts to secure Ms Betancourt's release. She is believed to be suffering from hepatitis B and leishmania, a skin disease caused by insect bites.

Bernard Kouchner, the French Foreign Minister, told reporters yesterday that Mr Sarkozy was ready to travel to Colombia if necessary and added that France could take in freed Colombian rebels in its Caribbean territories temporarily as part of a deal to free Ms Betancourt and other hostages. (AFP/AP)

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