Otunbayeva becomes central Asia's first female president

"As president, I will spare no effort to create a new political culture for the country based on a strict adherence to the rule of law," she told more than 1,000 cheering supporters. "I must be principled and consistently make demands on all branches of government to ensure it. The new policy cannot be built on fantasies and illusions. It must become real and effective."

As well as being ex-foreign minister, Otunbayeva was once ambassador to Britain. She and her political allies took power after demonstrations and riots that ousted president Kurmanbek Bakiyev in April.

Following a referendum which won a massive majority, she is caretaker president with reduced powers until an election next year in which she cannot stand. Parliamentary elections are set for October.

Otunbayeva blamed recent anti-Uzbek violence in the south on “dark forces” but refrained from endorsing claims that armed Kyrgyz militias were behind it.

"Today Kyrgyzstan is going through one of the most dramatic periods in its history. Unfortunately, tragic events took place in the Osh and Jalalabad regions.... Dark forces have spilled blood of many innocent people," she said.

"For my part, I give my word that the state will do everything possible, as soon as possible to overcome the consequences of the tragedy."