WASHINGTON — FCC chairman Reed Hundt has formally agreed to defer a vote on an agency probe of liquor advertising on television.After waiting two days, Hundt agreed to yank the issue at the request of FCC commissioner Rachelle Chong. If Hundt had failed to honor Chong’s request, it would have been the first time in FCC history that a chairman refused a request by a fellow commissioner to defer the vote. Hundt wants his agency to take a close look at hard liquor advertising, but is running into trouble because two out of four commissioners adamantly oppose the investigation. In addition to Chong, commissioner James Quello opposes the inquiry, claiming that the FCC has no jurisdiction over advertising. Both Quello and Chong say the Federal Trade Commission has sole responsibility for regulating the advertising industry. Not willing to go quietly, Hundt’s office released a letter Monday from Attorney General Janet Reno which called on the FCC to conduct an investigation. “The (FCC) should explore whether liquor advertising over the electronic media poses a risk to children and to other groups that may be particularly susceptible to alcohol abuse,” wrote Reno. Hundt said Monday that he hopes to reschedule the vote for July.