The Colombian President, Mr Andres Pastrana, in a televised address to the nation, has said he would be "firm" and take into account growing outrage over rebel violence when a key peace deadline arrives next week.
Mr Pastrana appeared stern but vague in his address on Wednesday and did not say whether he would extend rebel use of an enclave, as big as Switzerland, that he ceded to the Marxist FARC guerrillas more than two years ago, to launch peace talks.
But Mr Pastrana expressed concern over FARC violence and Saturday's murder by FARC rebels of former culture minister and popular musical personality Consuelo Araujo (56), also the attorney general's wife.
"I am dying of sadness over the villainous murder of my friend," Mr Pastrana said.
The Revolutionary Armed Forces of Colombia, known by its Spanish initials FARC, are branded a "terrorist" organisation by the United States. The group relies mainly on "taxing" Colombia's cocaine trade to fill war chests.
Mr Pastrana, as a negotiating tool, has given the FARC the right to use the demilitarised zone more than a half dozen times, extending the deadline in each instance.
Despite ceding the swath of land, Colombia's 37-year guerrilla war rages on, infuriating a public which accuses the president of literally letting the FARC get away with murder.