PML-N president and Leader of the Opposition in the National Assembly Shehbaz Sharif has tested positive for the novel coronavirus, party spokesperson Marriyum Aurangzeb confirmed on Thursday.

Sharif has isolated himself at home, she added.

Party leader Ataullah Tarar also confirmed the development and said Sharif's "life had been endangered in this situation by NAB's summoning of him".

"NAB was informed multiple times in writing that Shehbaz Sharif has suffered from cancer and compared to other people, his immunity system is weak," Tarar said and added that Sharif had only left home to appear before NAB.

"Imran Niazi and NAB will be responsible if something happens to Shehbaz Sharif," he said.

When asked about the news, Hamza Shehbaz, Sharif's son and PML-N leader, said: "This is a difficult time for Pakistan. May Allah grant health to everyone's parents."

In a statement issued later in the day, Shehbaz urged the public to be "extraordinarily careful", adding that he had been "extremely careful" and followed the advice given to him by medical professionals.

"Except for a couple of unavoidable outings recently like appearance before NAB, I have been home and conducted most of the meetings online," he said in a tweet.

The PML-N president had appeared before the National Accountability Bureau on Tuesday in connection with investigations pertaining to money laundering and income-beyond-means.

Earlier this month, he had also appeared before the Lahore High Court to obtain a pre-arrest bail in cases regarding money laundering and assets beyond means. Sharif had filed the appeal in the high court a day before a NAB team raided his residence to arrest him on June 2, after he refused to appear before the accountability watchdog.

Sharif had thrice refused to appear before NAB citing health reasons. In a statement submitted to the bureau, he said: "It has been widely reported in the media that some NAB officials have tested positive for Covid-19.

"Please appreciate [that] I am a cancer survivor and 69 years old. I have been advised limited exposure on account of the peculiar background of low immunity," he said.

He added that he was available to answer any queries by the investigation team via Skype.

Sharif is the latest PML-N leader to have tested positive for the virus. Multiple other members of PML-N's top-tier leadership have been diagnosed with the disease, including Aurangzeb, Tariq Fazal Chaudhry, Ahsan Iqbal and former prime minister Shahid Khaqan Abbasi.

PTI's Khurram Sher Zaman tests positive

President of PTI Karachi chapter and member Sindh Assembly Khurram Sher Zaman has also tested positive for Covid-19, he said in a tweet.

Zaman has been vocal about his opposition to a lockdown in Sindh to curb the spread of the disease and had criticised the PPP for insisting on imposing one. Last month, he said that the PTI will "stand against" the PPP government if it decides to further extend the lockdown in Sindh's urban areas.

Multiple politicians, including members of the ruling PTI, have been diagnosed with the virus in Pakistan as the government insists on easing lockdown against doctors' advice. More than 117,000 people have tested positive across the country since the first case emerged on Feb 26.

Prominent political leaders who have contracted the virus so far include National Assembly Speaker Asad Qaiser, Sindh Governor Imran Ismail and PPP leader Saeed Ghani, all of whom have recovered.

Last week, MQM-P leader Faisal Sabzwari was diagnosed with the virus, along with his parents, wife and daughter. Before that another federal minister, Shehryar Afridi, had also tested positive and gone into isolation.

On Monday, Railways Minister Sheikh Rashid confirmed he had tested positive, adding that he was experiencing no symptoms and that he had isolated himself at his home.

Muttahida Majlis-e-Amal MPA Abdul Rasheed and Senator Mirza Mohammad Afridi are also among politicians who have tested positive.

Former Balochistan governor Syed Fazal Agha, PTI Punjab MPA Shaheen Raza, Sindh Minister for Human Settlement Ghulam Murtaza Baloch, MNA Munir Khan Orakzai and PTI's Mian Jamshedud Din Kakakhel are among politicians who passed away after contracting the virus.