Deposed Honduran President Jose Manuel Zelaya on Monday gave the interim government that ousted him an ultimatum: if ongoing negotiations do not restore him to power, he will consider the talks failed and resort to other means. Zelaya's remarks came at a news conference in Managua, Nicaragua. He did not elaborate on what other means he might explore. The statement puts pressure on the next round of mediation between the two sides, expected to take place Saturday in Costa Rica, according to a report of CNN. Zelaya demanded that "the explicit mandates of the international organizations be carried out," referring to resolutions passed by the Organization of American States and United Nations calling for his return as president. Since the June 28 military-led coup, Zelaya and interim Honduran President Roberto Micheletti have drawn hard stances. Both claim that the democratic process is on their side. Both Micheletti and Zelaya accepted an offer from Costa Rican President Oscar Arias to mediate talks. Both men met individually with Arias last week, but they did not meet face-to-face. Micheletti said Monday he expected talks between the two delegations to resume on Saturday in Costa Rica. United Nations Secretary-General Ban Ki-moon spoke with Arias Monday and gave his support for his mediation efforts. "The Secretary-General has offered technical assistance for the mediation and agreed to work together with President Arias to help the parties reach an agreement," a U.N. statement said. "The Secretary-General is confident that an open dialogue and international support will help resolve the current crisis."