Condemning the deadly bombing of a Shia mosque in Pakistan, UN Secretary-General Ban Ki-moon has called on the country to step up efforts to protect religious minorities and combat terrorism.

In a statement issued by his spokesperson, Ban said he is appalled by such vicious targeting of people on account of their religious affiliation.

He condemned the bombing of the Shia mosque in Pakistan's Sindh province on Friday, which killed at least 61 people gathered for prayer.

The Secretary-General "calls upon the authorities to redouble their efforts to protect religious and ethnic minorities in Pakistan and to combat terrorism in all its forms".

He extended his condolences to the families of the victims and sympathies to the government of Pakistan.