Egypt's former President Hosni Mubarak, hospitalised since April and due to stand trial in August, is in a coma, his lawyer said.
The state news agency MENA has cited a hospital official as denying the report.
The official said 'Mubarak suffered a sudden loss of blood pressure but quickly returned to normal again after the necessary medicines were given to him. His medical condition is stable.'
Another medical source said Mr Mubarak, 83, occasionally slipped into a coma but his condition was stable.
Mr Mubarak's condition has been subject to frequent speculation in the Egyptian media, gaining momentum before his 3 August trial.
Protesters have been camped out in Cairo's Tahrir Square since 8 July and have protested in other Egyptian cities.
Their demands have included calls for the military council now ruling Egypt to speed up Mubarak's trial.
The former president, who is hospitalised in the Red Sea resort of Sharm el-Sheikh, faces charges of abuse of power and killing protesters.
More than 840 protesters died in the 18 days of demonstrations that led to him being ousted on 11 February.
Some Egyptians have questioned Mr Mubarak's illness, seeing it as a ploy for the army to avoid putting on trial the former air force commander who ruled Egypt for 30 years.
Mr Mubarak had generally enjoyed good health in office. He underwent gallbladder surgery in Germany in March 2010 but he had appeared to make a full recovery.
When in office, officials routinely dismissed talk of ill health including cancer reports.
Meanwhile, Prime Minister Essam Sharaf announced on his Facebook page that Mohammed Kamel Amr, a former senior diplomat who has worked at the World Bank, was appointed Egypt's new foreign minister.
The appointment to replace Mohammed al-Orabi comes as part of a sweeping cabinet shuffle aimed at appeasing protesters angry at the slow pace of reform since the February ouster of president Hosni Mubarak.