Pakistan has rejected United States Secretary of State Condoleezza Rice's request to allow America to question disgraced scientist A Q Khan over his alleged role in Iran's nuclear programme, a report said on Tuesday.

Rice, who was in Pakistan late in March, requested direct American access to Khan 'so that the US intelligence community could ask him about his nuclear handiwork in Iran'.

• Pakistan's nuclear bazaar

But all she obtained was permission to submit a list of questions to Khan, The Washington Times said.

It also said that both the US and Israel 'have contingency plans to launch air strikes against Iran's 12 to 15 nuclear sites, most of them underground'.