By Mehreen Zahra-Malik

ISLAMABAD (Reuters) - Pakistan's government on Monday vowed to block protests in Islamabad if opposition leader Imran Khan pushes ahead with plans to shut down the government and transport in the capital from Nov. 2.

The threatened protest has prompted worries of a repeat of a crippling occupation of Islamabad that Khan led in 2014 after he rejected Prime Minister Nawaz Sharif's election win.

Khan has demanded that Prime Minister Nawaz Sharif resign over the Panama Papers data leak that linked the premier's family to offshore wealth. Sharif's family denies any wrongdoing.

The opposition leader has seized on the Panama Papers scandal as a fresh opportunity to try to unseat Sharif.

However, government spokesman Pervaiz Rashid said on Monday there would be no repeat of 2014, as Khan vowed the same day that a million people would protest.

"It is the government's responsibility to ensure that life in the capital goes on as normal," Rashid told a press conference in Islamabad. "The law will take its course against elements trying to shut down Islamabad."

Rashid was not explicit how the government would thwart the protests.

A former cricketing hero, Khan said the protests would force the closure of schools, public offices, roads into the capital, and the airport, until Sharif resigned or agreed to be investigated.

"No police can stop one million people," Khan told a rally on Monday.

"Nawaz Sharif ... for seven months you have neither agreed to being investigated nor resigned," Khan added. "Now you can't run away from November 2."

Leaked documents from the Panama-based Mossack Fonseca law firm appeared to show that Sharif's daughter and two sons own offshore holding companies registered in the British Virgin Islands. Sharif's family deny wrongdoing.

Holding offshore companies is not illegal in Pakistan, but Khan has implied the money was gained by corruption.

Members of Sharif's cabinet addressed a press conference on Saturday and accused Khan himself of money laundering and tax evasion. His party did not respond to calls seeking comment.

The allegations follow Khan's acknowledgement in May that he used an off-shore company to legally avoid paying British tax on a London property sale. The admission temporarily eased the pressure on Sharif's government but the opposition is once again using the Panama Papers to try and unseat Sharif.

(Writing by Mehreen Zahra-Malik,; Editing by Kay Johnson and Richard Balmforth)