bogota colombia leftist eln rebel say sunday will extend ceasefire set expire next month sufficient progress peace talk government national liberation army eln government public peace talk quito 10 months long exploratory phase negotiations bid end 53 years war group first-ever ceasefire begin october set expire jan. 9. supervise catholic church unite nations will agree new ceasefire jointly evaluate negotiate table progress confidence result current one group say open letter u.n. post eln twitter account eln add would also assess government willingness overcome hurdle talk 2,000-strong eln regularly bomb oil infrastructure take hostages continue kidnap despite ceasefire indigenous leader choco province die october detain group colombia 's eln rebel will extend ceasefire talk progress