His stance has stoked international concerns about the future of the tiny west African country.
Jammeh, who has been in power for 22 years, stunned observers by initially accepting his defeat in the December 1 vote by opposition candidate Adama Barrow, but then flip-flopped a week later, rejecting the results and filing a court challenge.
His stance has stoked international concerns about the future of the tiny west African country, with the UN joining African leaders in calling for him to step down.
"My rights cannot be violated and intimidated to a point where I succumb to blackmail," Jammeh said in a lengthy televised address, referring to diplomatic efforts by the west African ECOWAS bloc.
"Unless the court decides the case, there will be no inauguration (of Barrow) on the 19 January," Jammeh added, referring to his petition to the Supreme Court to overturn the election result.
"What we are asking for is not for the IEC (Independent Election Commission) to declare me the winner, I cannot do that," he said late Tuesday.
"I will not cheat but I will not be cheated. Justice must be done and the only way justice can be done is to reorganise the election so that every Gambian votes. That's the only way we can resolve the matter peacefully and fairly."
Experts say Jammeh has bought time by taking his appeal to the Supreme Court, which has lain dormant since May 2015.
All its judges were fired under Jammeh's orders save its chief justice, Nigeria-born Emmanuel Fagbenle.
But court sources say six foreign judges, besides Fagbenle, have now been appointed by Jammeh to serve on the Supreme Court to hear his complaint.
Complicating matters, the target of Jammeh's complaint, the Independent Electoral Commission that he says made errors requiring a fresh election, is represented by Jammeh's own attorney general.
Even Gambia's own bar association has denounced the system as "fundamentally tainted".
Fagbenle announced on Wednesday that Jammeh's case had been adjourned until January 10 because the chief defendant -- the IEC -- had not been summonsed to attend, dashing any hopes of a quick resolution to the crisis.
In a fiery monologue, the 51-year-old Jammeh, who took power in a bloodless coup in 1994, denounced ECOWAS and foreign powers who support it for interference in Gambian affairs.
Leaders of ECOWAS -- including Senegal, which surrounds the landlocked country save its coastal border -- said at the weekend they would attend Barrow's inauguration and "take all necessary actions to enforce the results", without spelling out what those measures might be.
"ECOWAS is trying to force me out," Jammeh said in the televised remarks. "It will not happen... And let me see what ECOWAS and those big powers behind them can do."
Jammeh initially warmly congratulated Barrow after results were declared on December 2.
But a week later he condemned "unacceptable errors" by election authorities and called for a new vote.
"I will not step down, because this is disrespectful of our constitution which says a transition period of 60 days. Even if he had won legally, I have 60 days of transition," he said Tuesday.
The nation's government-in-waiting said on Monday that Jammeh had no constitutional mandate to stay in office beyond January.
"Any president who loses constitutional legitimacy becomes a rebel," said Halifa Sallah, a spokesman for the opposition coalition that spurred Barrow to victory.
But the opposition has also said Jammeh would not face prosecution on leaving office.
Under Jammeh's long rule, The Gambia has remained crushingly poor but enjoyed relative stability -- though rights groups and media watchdogs accuse him of cultivating a climate of fear and crushing dissent.