Johannesburg - Zimbabwe’s President Robert Mugabe has slammed the two-term limit imposed on African leaders, but at the same time made fun of Burundi’s president Pierre Nkurunziza’s third-term bid.Speaking at the opening session of the African Union assembly of heads of state in Sandton on Sunday afternoon “we [in Africa] put a rope around our own neck and say leaders must only have two terms”.Mugabe, who is serving his seventh term, but his first under Zimbabwe’s new constitution which restricts him to two terms, added that leaders in Europe did not face the same term limits, yet they are still considered to be democracies. “It is a democracy, if people want a leader to continue, let him continue,” he said, adding that two terms could feel as short as two weeks.But he warned against causing instability by seeking more than two terms.He appeared to make fun of Burundi’s Pierre Nkurunziza, who said his first term shouldn't count towards his constitutional two-term limit because he was chosen by parliament and not by the people. “They say the first term was not a real term. But you were there for five years!” Mugabe said. There have been calls from within AU member states for Nkurunziza not to seek a third term, while the AU's Peace and Security Council last night called for an urgent intervention in Burundi to prevent the conflict around the upcoming elections from deteriorating into civil war.He also spoke out against leaders seeking retaliation. “Then there are fights. You beat me yesterday, I beat you tomorrow, and you overthrew me yesterday, now we’ll overthrow you also. Things continue to happen. Let’s be brotherly, principled and avoid causing problems to our people, because then our people become refugees,” he said.Mugabe returned to his scripted speech after being passed a note by an aide. Earlier in his speech he slammed the west for its thirst for mineral resources. He slammed former US president George W Bush and former British president Tony Blair for the war in Iraq and for taking out former Iraq ruler Saddam Hussein because of oil. “When they look at their little British island, left with nothing to offer, except a little coal, which they are burning,” he said, to laughter and applause by delegates.Mugabe sympathised with Hussein, who he said was vilified as a dictator with weapons of mass destruction because the west wanted his oil.He had delegates in more hysterics by saying “little Bush” and “little Blair” played follow my leader, and went off to war in Iraq.Mugabe was making these remarks as there are calls for the arrest of Sudanese president Omar al-Bashir’s arrest after he flew to South Africa, which is a signatory to the Rome Statute. This obliges South Africa to arrest Bashir, who wanted by the International Criminal Court for war crimes and crimes against humanity.The AU has been increasingly hostile towards the ICC, with many making the argument that the US and Britain have been equally guilty of war crimes in Iraq.