Mass anti-government street rallies by the political party of former Pakistan cricketer Imran Khan have been banned.
But a court has allowed protests as long as they are confined to a park in the capital, Islamabad, far away from the main government and commercial areas.
The high court warned that the rallies should not cause any disruptions, but rejected a government call to ban all demonstrations.
Police have detained at least 1,500 activists linked to Mr Khan’s Pakistan Tehreek-e-Insaaf party (Movement for Justice) and have clashed with supporters trying to get into Islamabad.
Five Kalashnikov rifles, a pistol, six magazines, a bulletproof vest, alcohol and three tear gas shells were recovered from a car belonging to Movement for Justice senior leader Amin Gandapur, according to police.
Protesters have faced baton-charges and tear-gas near Mr Khan’s home.
There have also been clashes in Rawalpindi, Karachi and Lahore,
Mr Khan said police are not allowing him to leave his home but added that he was not afraid of arrest.
“Even if you send me to jail, I will come back to lead rallies against you,” he said, addressing Mr Sharif.
The party has called for a massive “million-men” march on Wednesday, when Mr Khan was reported to have said the city would be shut down to try to force the resignation of Prime Minister Nawaz Sharif.
He has since said his rallying cry to stop the government from functioning was not a direct threat, but a prediction of what would happen if his supporters flooded into the city.
Mr Sharif has come under mounting pressure after members of his family were named as holders of offshore bank accounts in financial documents leaked as part of the so-called ‘Panama Papers’ scandal.
Mr Khan was formerly married to British heiress Jemima Khan, the sister of politician Zac Goldsmith.
“The whole state machinery is being used to save a corrupt Prime Minister,” said Mr Khan.
“I will not accept a ‘suspect’ as prime minister of Pakistan.”
In April, documents from the Panama-based Mossack Fonseca law firm appeared to show that Mr Sharif’s daughter and two sons owned offshore holding companies registered in the British Virgin Islands.
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Holding offshore companies is not illegal in Pakistan, but Mr Khan has implied the money was gained by corruption.
Mr Khan himself admitted in May that he used an offshore company to legally avoid paying British tax on a London property sale.
Mr Sharif’s family denies wrongdoing, and the case is due to be considered by Pakistan’s Supreme Court on Tuesday.