Gambia's President-elect Adama Barrow is scheduled to be sworn in on Thursday, but the incumbent, Yahya Jammeh, is refusing to step down.
Jammeh this week announced a state of emergency which the national assembly approved, keeping him in power for another 90 days.
West African countries have sided with the president-elect after Barrow won the December election.
The African Union and West African regional body ECOWAS (Economic Community Of West African States) have said that as of Thursday they will only recognise Barrow as Gambia's president.
Gambia’s vice president Isatou Njie Saidy who had been in this role since 1997, had quit on Thursday afternoon, according to reports.
TRT World's Fidelis Mbah discusses the situation.
- Nigeria: Warship off Gambia's coast and air force deployed to Senegal in case it's needed.
- Senegal: Army on standby on Gambia's border.
- Ghana: 250 combat troops to enable Barrow to be sworn in.
Last Minute Talks
Senegal's deployment of troops along the border with Gambia raised the prospect of armed confrontation between forces loyal to the president, who has ruled Gambia for 22 years, and Senegal, which surrounds the tiny riverside country on three sides.
Senegal circulated a draft resolution to the 15-member UN Security Council that would give "full support to the Economic Community Of West African States (ECOWAS) in its commitment to take all necessary measures to ensure the respect of the will of the people of Gambia."
Barrow's spokesperson Halifa Sallah said Barrow, who's in Senegal, could not be sworn in and take the oath of office at an undisclosed place.
Diplomats said Barrow could be sworn in at the Gambian embassy in Senegal.
It is not immediately clear when Senegal planned to put the draft resolution to a vote.
Some diplomats said UN Security Council approval was not needed for an ECOWAS military intervention if Barrow requested help.
As a last ditch effort, Mauritanian President Mohamed Ould Abdel Aziz arrived in Gambia late on Wednesday for last-minute talks ahead of the deadline.
Aid agencies say thousands are fleeing the country due to fears of unrest.
At least 26,000 people have fled from Gambia to Senegal, the UN High Commissioner for Refugees (UNHCR) said on Wednesday, citing Senegalese government figures.
The UNHCR said up to 80 percent were children accompanied by women.
TRT World's Christine Pirovolakis has more.