Former Yugoslav President Slobodan Milosevic has said accusations that he masterminded the 1990s wars in the Balkans were "unscrupulous lies".
The trial has suffered many delays due to Milosevic's ill health
Mr Milosevic, who is representing himself, was making his opening defence statement at his trial in The Hague.
The trial resumed on Tuesday, after his poor health caused numerous delays.
Mr Milosevic faces charges of genocide, crimes against humanity and war crimes for his alleged role in the conflicts in which tens of thousands were killed.
He made a sweeping opening statement heavy on historical details - for which he was chided by presiding judge Patrick Robinson, who said he was taking up much time dealing with history.
He portrayed the Serbs as the victims of a plan supported by the US and Europe to break up the former Yugoslavia, says the BBC's Geraldine Coughlan in The Hague.
"They supported a totalitarian chauvinist elite, terrorists, Islamic fundamentalists, neo-Nazis whose objective was an ethnically pure state, that is to say a state without any Serbs," he told the court.
The trial has now adjourned for the day, but judges granted Mr Milosevic an extra 90 minutes on Wednesday to finish summarising his case after he complained he had only been given four hours.
Prosecutors were given three days to outline their case when the trial began in February 2002, he said.
Mr Milosevic blamed "the Nato pact" for the conflict in Kosovo, where the prosecution says Mr Milosevic was individually responsible for "the campaign of terror and violence directed at Kosovo Albanian civilians".
Began Feb 2002
Milosevic faces more than 60 charges
Prosecutors' case rested Feb 2004
Court already heard from 295 witnesses
Mr Milosevic compared events in Croatia at the start of the Balkan wars in 1991 to the "genocide of Serbs by Croatian fascists in 1941".
He said tens of thousands of Serbs were killed or driven from their homes in Croatia before the Yugoslav army responded
For a long time, an "untruthful and distorted picture" about what happened in Yugoslavia had been given to the international public, Mr Milosevic said.
"The accusations against me are unscrupulous lies and also a treacherous distortion of history."
He once again challenged the legality of the tribunal and of his trial.
On Wednesday, the three trial judges are to consider whether to impose a defence lawyer on him after he completes his opening statement, Reuters news agency reports.
The repeated delays caused by Mr Milosevic's ill health have prompted some to call for him to be forced to accept a lawyer - something he strongly rejects.
He has suffered from high blood pressure, flu and heart problems since the trial opened, although he appeared to be in good form on Tuesday.
Mr Milosevic says he wants to call more than 1,600 witnesses in the 150 days allotted to his defence - including former US President Bill Clinton and UK Prime Minister Tony Blair - although it is unlikely they will appear, say correspondents.
The first witnesses are not expected to be heard until next week.