Nicaraguan Ambassador Carlos Tunnermann had until late Friday afternoon to comply with a U.S. demand that he leave the country, but he was refusing to say whether he would. Tunnermann went before the Organization of American States' permanent council Thursday to make his case against the U.S. decision, accusing the Reagan administration of violating international law by expelling him. He declined to say whether he would leave in time to meet the 5:30 p.m. deadline imposed by the State Department. Most of the OAS delegates remained silent during the 100-minute meeting, with few willing to take a stand on either side of this latest chapter in the long-running U.S.-Nicaraguan dispute. Tunnermann did not ask the group to take any actions on his behalf, and no resolutions were introduced.