Jammeh, who is accused of serious rights violations, led his country for 22 years but refused to accept defeat in a December election. He flew out of the capital Banjul late on Saturday as a regional military force was poised to remove him.
Jammeh's decision to step down has prompted speculation over the terms agreed during two days of negotiations led by Guinea's President Alpha Conde and Mohamed Ould Abdel Aziz of Mauritania.
Speaking to Reuters, Senegalese Foreign Minister Mankeur Ndiaye said:
'The regional leaders had not gone as far as agreeing immunity despite Jammeh's attempts to secure this"He add that:
"President Jammeh and his team concocted a declaration to be endorsed by (regional bloc) ECOWAS, the United Nations and the African Union that gave him every guarantee, essentially impunity."
"This declaration was signed by no one."The foreign minister made his comments after the AU and the UN published a joint declaration from the three bodies "with the purpose of reaching a peaceful resolution to the political situation in The Gambia."
In it, they pledged, among other things, to protect Jammeh's rights "as a citizen, a party leader and a former Head of State", to prevent the seizure of property belonging to him and his allies, and to ensure he can eventually return to Gambia.