UNITED NATIONS, Jan. 20 (Xinhua) -- The UN Security Council on Thursday urged all Gambian parties and West African countries to ensure peaceful transition of power in Gambia.

In a unanimously adopted resolution, the 15-nation council requests former President Yahya Jammeh to transfer power to President Adama Barrow by Jan. 19, 2017 in accordance with the Gambian constitution.

Earlier on Thursday, Adama Barrow was sworn in as Gambian president at the Gambian embassy in Dakar, capital of Senegal.

Barrow, staying in Dakar since Saturday, won Gambia's presidential election on Dec. 1, 2016. However, his election win was challenged by Jammeh who refused to cede power to him despite decisions by the Economic Community of West African States (ECOWAS) to send troops to support Gambia in power transition.

UN Secretary-General Antonio Guterres Thursday called Barrow to discuss latest developments in Gambia and congratulated him on his inauguration, according to a statement by UN Spokesperson Office.

"The Secretary-General told President Barrow of his full support for his determination, and ECOWAS's historic decision, with the unanimous backing of the Security Council, to restore the rule of law in The Gambia so as to honour and respect the will of the Gambian people," said the statement.

"The Secretary-General conveyed the readiness of the United Nations system to support President Barrow and his government in their efforts to promote democracy and achieve sustainable development in The Gambia," it added.