0314 GMT June 23, 2018
In an address on state television on Tuesday, President Jammeh denounced the "unprecedented level of foreign interference in our elections and internal affairs and also a sustained smear campaign, propaganda and misinformation."
Jammeh also urged the Gambians to resolve the political crisis in the country themselves.
"I believe we can ask Gambians to come together to resolve this and any other matter without undue external interference," he said.
Three leaders from the Economic Community of West African States (ECOWAS), led by Nigeria’s President Muhammadu Buhari, will visit the Gambia on January 13 to mediate a solution to the political impasse. The trip was initially slated for Wednesday.
The visit will be the second by ECOWAS leaders to the Gambia in less than a month.
West African leaders have repeatedly pursued mediation to ensure a peaceful transfer of power in the Gambia. Last month, after a visit to the country, they declared that ECOWAS did not yet intend to deploy its standby military force and sought a peaceful transfer of power.
Nevertheless, if Jammeh refuses to step down by January 18, when his term expires, ECOWAS may use military intervention.
Jammeh has slammed the UN Security Council, the African Union and ECOWAS, which have called on him to concede defeat in last month's election, for taking "unprecedented and hasty resolutions against our republic and constitution."
The incumbent president has also ordered that "nobody be arrested or prosecuted" for acts during the pre and post election period.
He has also called for patience, urging the Gambians to "await the Supreme Court review and ruling on the election results." The earliest ruling in the case is expected in May.
Jammeh, who has been in power for 22 years, lost the December election to the opposition coalition’s candidate Adama Barrow by a thin margin.
The veteran leader initially conceded, but later changed his mind and called for a new vote, saying he would challenge the result in the Supreme Court.
Barrow has nevertheless asserted that his inauguration will go ahead regardless of the court case.