Bogota  - French Foreign Minister Bernard Kouchner asked Colombian President Alvaro Uribe to make more efforts to secure the release of former presidential candidate Ingrid Betancourt, kidnapped by leftist rebels six years ago.

Colombian media reported Tuesday on the contents of the meeting, which took place late Monday at the government palace in Bogota.

Uribe reportedly praised the role of France in seeking the release of Betancourt - who holds dual French-Colombian citizenship and is the most high-profile hostage held by the Revolutionary Armed Forces of Colombia (FARC).

However, he further called for a greater involvement by Switzerland and Spain.

Colombia was the first stage in a tour of the region that was also set to take Kouchner to Ecuador and Venezuela.

Uribe and Kouchner did not discuss the possibility that Venezuelan President Hugo Chavez would be granted another mandate to mediate with FARC. The Colombian president had already refused to contemplate such an option before the meeting with Kouchner.

The left-wing populist Chavez was called in to mediate in the Colombian conflict - with Uribe's support - in mid-2007, but Uribe terminated his mandate some two months later. Chavez persisted in his efforts, however, and obtained the release of a total of six hostages held by FARC so far this year. However, the rebels have stressed that there will be no further liberations outside a prisoner exchange agreement.

Betancourt, 46, has been held by FARC since February 2002 and is reportedly very weak following a hunger strike.

On April 1, French President Nicolas Sarkozy sent a video message to the rebels asking them to release Betancourt, whose life he said was in danger.

Sarkozy sent a medically-equipped plane to Colombia, in the hope that the team might be allowed to treat Betancourt in the jungle. However, the mission returned to France empty-handed.

FARC intend to exchange 40 politically-relevant hostages (including Betancourt) for 500 rebels held in prison (including three who have been extradited to the United States). The group holds an estimated 740 people hostage. (dpa)