Updated

Pakistani opposition parties have urged the country's Prime Minister Nawaz Sharif to step down after a Supreme Court probe into corruption allegations against his family members found "significant disparity" between their declared wealth and known sources of income.

Babar Awan, a leader of cricket-star-turned-politician Imran Khan's party, said on Tuesday that Sharif's only option is to quit. Sirajul Haq, the leader of opposition Jamaat-e-Islami party, also demanded Sharif's resignation.

Investigators in the probe suggested on Monday that courts pursue action based on a 1999 accountability law intended to help eliminate corruption. But the final decision rests with the Supreme Court, which will take up the case next Monday.

Sharif has been under pressure since documents leaked in 2016 from a Panama-based law firm disclosed that his family had offshore accounts.