"Nuclear weapons should never fall into the hands of Islamists. Despite the current unstable situation, there is not yet any concrete risk (that it could happen) but the situation has to be put right for that to remain true," he told the Sunday weekly Bild am Sonntag.

"We will discuss what we can do to this end with the United Nations, the United States and the Europeans," he added.

"We are horrified by the cruel attack" which cost former prime minister Bhutto her life and "which has created a situation which could lead to the most serious crisis in the history of Pakistan," he said.

He called on Pakistani politicians "to work together now to stand up to the (Islamist) fundamentalists."

At least 33 people have been killed in Pakistan in rioting unleashed by Bhutto's asssassination on Thursday. The government has blamed al-Qaeda for her death.

All rights reserved. � 2005 Agence France-Presse. Sections of the information displayed on this page (dispatches, photographs, logos) are protected by intellectual property rights owned by Agence France-Presse. As a consequence, you may not copy, reproduce, modify, transmit, publish, display or in any way commercially exploit any of the content of this section without the prior written consent of Agence France-Presse.