LAGOS, Dec. 17 (Xinhua) -- The Economic Community of West African States (ECOWAS) has sent its mediating team to Niger for talks to end the political crisis, the News Agency of Nigeria reported on Thursday.

The West African country has been in turmoil since President Mamadou Tanja approved a referendum to extend his rule beyond limit.

An official of the Nigerian Ministry of Foreign Affairs confirmed in Abuja on Wednesday that Abdulsalami Abubakar, the chief negotiator, and his team was in Niamey for talks with stakeholders.

"They are in the country to continue their exploratory talks with the stakeholders in the crisis, which was caused by President Mamadou Tanja's decision to extend his tenure," the official told reporters on condition of anonymity.

"I cannot give you details of the ongoing talks, which started in November, but I can assure you that we will get a clearer picture when the delegation returns," the official added.

A 41-member opposition delegation from Niger met with Abubakar in November, in the wake of the crisis that rocked the country over President Tanja's decision to amend the country's constitution.

Tanja claimed then that the result of a referendum paved the way for him to change the country's constitution to enable him to remain in office for another three-year term, which could be extended without a vote.

The opposition delegation, which met with Abubakar in November, was led by Mahmadou Issoufu, the president of the main opposition Nigerien Party for Democracy and Socialism (PNDS).

Abubakar also met with the Nigerien government officials.

ECOWAS, the sub-regional economic bloc, and the African Union have imposed sanctions on Tanja's government for ignoring a warning not to conduct parliamentary elections.

Tandja, 71, who has been in power since 1999, has cracked down on the press and critics of his tenure-elongation after dissolving the Constitutional Court and the Parliament and assuming the power to rule the uranium-rich country by decree.

The ECOWAS Commission has been engaged in efforts to get the Nigerien authorities to abide by its constitution and the ECOWAS Additional Protocol on Democracy and Good Governance since the crisis began.