A legal adviser to Pakistani Prime Minister Nawaz Sharif says the premier has submitted a written response to the Supreme Court denying allegations he held offshore bank accounts.

Pakistan's Supreme Court is investigating Sharif and his family's financial affairs after documents leaked from a Panama-based law firm revealed they owned money offshore.

Zafar Ullah says that on Thursday the Court gave Sharif's children more time to respond to the allegations because some of them are overseas.

The latest development came a day after supporters of the opposition leader Imran Khan rallied in Islamabad to pressure Sharif to resign over his alleged financial corruption. Khan called off earlier plans for a mass protest rally intended to lock down the capital when the Supreme Court announced it was initiating its investigations.