Pakistan's Prime Minister Nawaz Sharif, who is in London for medical check-up, will undergo an open-heart surgery on Tuesday, according to his daughter.

Sharif's daughter Maryam Nawaz tweeted that her father will undergo the open-heart surgery.

"Prime Minister Nawaz Sharif undergoing open heart surgery on Tuesday. Prayers are the most effective and potent medicine. Millions will pray for him. Insha Allah he'll be fine," she tweeted last night.

Maryam went on to explain her 66-year-old father's medical condition, saying: "In 2011 Nawaz Sharif had a cardiac procedure called 'Atrial Fibrillation Ablation', during which certain complications occurred resulting in perforation of heart which was in turn treated by open heart surgery." Therefore, Sharif had been visiting his doctor for follow up, she said.

"After some recent symptoms a team of cardiologists and cardiac surgeons carried out some scans and tests, following which they decided to go for an open heart surgery," she said.

The prime minister will be on specific medication for the next three days before his surgery on Tuesday, Maryam said.

"The recovery period and hospital stay will be one week. Nawaz Sharif will travel back to Pakistan as soon as the doctors allow," she added.

Defence Minister Khawaja Asif also said doctors have advised Sharif to undergo an open-heart surgery, following which he will be staying in the hospital for a week in London.

"The prime minister will travel after one week, on doctor's permission," Asif, who is also a confidante of the premier, said here yesterday. This is Sharif's second trip to London for medical check-up in recent weeks.

He had undergone a check-up in Pakistan last month following which he decided to visit London for a proper medical assessment. He went to London on May 22 for a medical check-up and was supposed to return in a week.

His surgery will be conducted at London's The Princess Grace Hospital, which is considered one of the best-equipped multi-disciplinary hospital in the UK capital.

Sharif has been facing pressure from opposition political parties at home to conduct a thorough investigation into the Panama Papers leaked documents - which show that members of his family own undeclared offshore wealth and expensive property in London.

Some leaders in Pakistan have demanded Sharif to step down amid the scandal. Sharif and his family have denied any wrongdoing.