BOGOTA (Reuters) - The Colombian government said its peace negotiations with the National Liberation Army (ELN) were postponed to Jan. 10 while the guerrilla force conducts internal consultations and is to free a kidnapped politician.

Colombian President Juan Manuel Santos has said negotiations with the ELN, which the United States and European Union consider a terrorist organization, could only begin after the release of Odin Sanchez, who was kidnapped in April.

They were meant to start last month.

Santos, who won the Nobel Peace Prize in October, has wagered his legacy on bringing stability to Colombia and on Wednesday succeeded in getting an accord with the FARC guerilla force through Congress.

The ELN is the country's second largest-guerrilla force after the FARC.

The Colombian delegation in Quito said in a statement that the postponement stemmed from a request by the ELN.

"The government hopes that during these weeks, the ELN will not only carry out the requested consultations, but that, as soon as possible, Odín Sánchez will be released to his family," the statement said.

Santos and the ELN agreed in March to begin a formal dialogue in Ecuador after spending more than two years setting negotiation issues and logistics.

However, the dialogue did not begin as planned because the guerrillas refused to suspend kidnappings and attacks on economic infrastructure.

The ELN, which is also accused of assassinations and extortion of oil and mining multinationals, has about 2,000 combatants. It emerged in 1964, inspired by the Cuban revolution and supported by radical Catholic priests.

A half-century conflict with guerillas in Colombia has left 220,000 dead and millions displaced.

(Reporting by Luis Jaime Acosta; Writing by Girish Gupta; Editing by Lisa Von Ahn)