ElBaradei told German news weekly Der Spiegel in remarks published on Sunday that members of the Muslim Brotherhood camp of ousted president Mohamed Morsi should not be treated as criminals.

"I am calling for inclusion of the Brotherhood in the democratization process," he said in comments printed in German.

"No one should be taken to court without a convincing reason. Former president Morsi must be treated with dignity," he added, calling such principles "preconditions for national reconciliation".

Asked whether he feared becoming a "fig leaf" for the military, which deposed Morsi on Wednesday, ElBaradei insisted the generals were listening to his concerns.

"My red line is that I won't work with anyone who does not respect tolerance and democracy," he said.

ElBaradei said he expected new elections "at the latest in one year's time" and said he could accept another Muslim Brotherhood victory if it respected democratic principles.

He called on Germany, which has committed around 100 million euros ($128 million) to a so-called "transformation partnership" in Arab countries such as Egypt, to respect the decision to oust Morsi following criticism from Berlin of the move.

The Germans in particular know "how difficult it is to build a democracy after a dictatorship and they were the first ones to criticise Morsi's anti-democratic policies", he said, referring to Germany's experiences after the Nazi and communist regimes.

"Let me be clear - this was not a coup," he said. "More than 20 million people took to the streets because it could not continue like that."

The official MENA news agency said on Saturday that caretaker president Adly Mansour had appointed ElBaradei as interim premier, only for his office to later deny any final decision had been taken.