Pakistan says it is placing its madrassas, or Islamic religious schools, under closer scrutiny.
Shezhad Tanweer is thought to have attended a madrassa
The move comes amid reports that one of the bombers who attacked London last week spent some time in one.
Pakistan's authorities will not confirm whether the bomber did attend a school run by a banned militant organisation during a visit to Pakistan last year.
The authorities also denied claims that they have started arresting suspects in connection with the London attacks.
On Sunday, Pakistan's ambassador to the United Nations, Munir Akram, said Britain should try not to blame foreign countries for influencing the London suicide bombers.
Pakistan's Interior Minister Aftab Khan Sherpao told the BBC in an interview that far closer scrutiny would be paid to madrassas espousing extremist lines of thinking.
Mr Sherpao said action would be taken against jihad preaching
This after speculation that London bomber, 22-year-old Shezhad Tanweer, had visited one in the eastern city of Lahore.
The Pakistani authorities have not confirmed the visit and the madrassa itself, which is believed to have links to a banned militant organisation, has furiously denied that Tanweer ever studied there.
Mr Shapao said the government would take action against any madrassa that preached jihad or indoctrinated young minds.
He refused to be drawn on the results from the Pakistani investigation into the backgrounds of those London bombers believed to have been in Pakistan recently.
He also said government leaders would meet soon to discuss how to implement President Pervez Musharraf's instruction to enforce the squeeze on Pakistani militant organisations.
The president ordered the security forces to move against the leaders of militant organisations preaching hatred during public appearances and to stop the dissemination of literature and videos promoting religious hatred.
Such material is easily available in markets across the country.
Analysts say the instructions, issued on Friday, were a tacit admission that the campaign against extremist groups left plenty to be desired with several leaders associated with the militant fight in Kashmir still at liberty and appearing openly around the country.