TRENTON, N.J. ? Gov. James E. McGreevey began suffering fallout from his bombshell resignation announcement Friday as his former homeland security adviser accused the governor of sexual harassment and Republican leaders called on him to leave office immediately.

“While employed by one of the most powerful politicians in the country, New Jersey Governor McGreevey, I was the victim of repeated sexual advances by him,” Golan Cipel said in a statement read by his attorney during a news conference in New York. The attorney added that McGreevey had made Cipel the victim of a “smear campaign.”

McGreevey announced his resignation Thursday in a dramatic, nationally televised news conference in which he revealed he had an affair with another man. His spokesman, Micah Rasmussen, vehemently denied Cipel’s accusations, calling them “completely and totally false allegations from a person trying to exploit his relationship with the governor. The matter has been referred to federal authorities for investigation.”

McGreevey did not name the man in his news conference, but two sources close to the governor, both speaking on condition of anonymity, said it was Cipel. One of the sources, a high-ranking member of the McGreevey administration, said Cipel threatened McGreevey with a sexual harassment lawsuit unless he was paid millions of dollars.

McGreevey named Cipel as New Jersey’s $110,000-a-year director of homeland security in 2002. But Cipel was transferred to a different position later that year after a storm of opposition from lawmakers who questioned his qualifications and later left state government.

Cipel, a poet and former lieutenant in the Israeli Navy, landed the job despite having no security experience, and he raised concerns among government agents who reportedly refused to share information with him because was a foreigner with no security clearance.

The saga took another strange turn Friday as Cipel alleged “intimidation” by McGreevey representatives cowed him into keeping quiet about the affair until now. Cipel attorney Allen M. Lowy said his client was offered money by representatives of McGreevey after the governor was informed of a possible lawsuit. He said “only time will tell” whether a lawsuit against McGreevey would be filed.

“After a long period of pain and introspection, I realized that in order to live my life, to move forward with my life, I needed to put this behind me. But the only way to do this was to have Gov. McGreevey take responsibility publicly for his horrible actions, which he did by resigning from public office,” Cipel said.

The developments occurred as Republican leaders called on McGreevey to leave office immediately, saying that news of the affair is likely to be first of many damaging disclosures.

“It is my suspicion that there will be more awkward stories in the days and weeks to come — stories that will make it very difficult for him to carry out the duties of his office,” said state Republican Chairman Joe Kyrillos.