The International Criminal Court in The Hague, The Netherlands Reuters/Jerry Lampen

The African Union (AU) has approved a plan for a mass withdrawal from the International Criminal Court (ICC), which some African leaders have accused of not being impartial. The non-legally binding decision came behind closed doors near the end of the AU summit in Ethiopia's capital Addis Ababa.

A draft of the plan recommends that African countries strengthen their own judicial mechanisms and increase the jurisdiction of the African court of justice and human rights to reduce "the deference to the ICC", AP reported.

A source close to AU said the debated was quite divisive on whether there should be an individual or collective withdrawal.

There are currently 34 African countries that are signatories of the Rome Statute, the treaty which set up the court in 2002.

South Africa and Burundi have already announced their withdrawal, claiming, among other things, that the ICC was biased towards African countries.

In 2015, South Africa said it was considering leaving the ICC following widespread criticism for its refusal to arrest Sudan president Omar al-Bashir, wanted by the ICC for alleged crimes including genocide committed during the Darfur conflict which began in 2003. Bashir has always rejected the charges and refuses to stand trial as his country does not recognise the ICC's jurisdiction.

Under the Rome Statute, South Africa as an ICC member has an obligation to arrest anyone sought by the tribunal. The government cited "contradictions" in the statute that clashed with treaty obligations to the African Union.

Gambia, under the leadership of former leader Yahya Jammeh, also announced it would pull out from the organisation, arguing the court "ignores war crimes" committed by Western countries. But new leader Adama Barrow said he will revert the decision.

Kenya, which the ICC is currently investigating, said it was watching the the withdrawals "with very keen interest."

However, not all African countries are in favour of a mass withdrawal. Last November, the Nigerian government restated its commitment to the ICC, which it said it represented the hope and aspirations of millions of people.

Botswana made similar remarks, urging countries not to leave "the only permanent international criminal tribunal."