The lengthy discussions on penalties, diplomatic sources said, finished with a ceiling of a 30-year jail term and the inclusion of perpetuity only on appeal, for exceptional cases.

This was described as a major achievement for the majority of states that favoured severe punishment for the heinous crimes at the ICC, but who wish to encourage rehabilitation rather than revenge.

The death penalty was not included in the Statute, but it is subject to further debate if countries that favour its inclusion so wish, the sources said.

Several experts have pointed out that Islamic and Caribbean countries, whose legal codes allow the penalty, would not like to see legal precedents being created to ban it in international law and were therefore reluctant to yield on the matter. This was despite reassurances that - under the principle of complementarity - their right to execute people remained on safe legal ground.

More than 100 countries have explicitly opposed the inclusion of the death penalty in the Statute, of which 70-odd are de jure abolitionists.