Suggestions that Egypt's President Hosni Mubarak is likely to announce he is standing down within hours have brought excitement to the protesters in Tahrir Square in central Cairo, but reports say their joy may be premature.

"The president is still in power and he is not stepping down. The president is not stepping down and everything you heard in the media is a rumour," Egyptian Information Minister Anas el-Fekky told Reuters news agency.

Some sources are backing up the reports but others deny it, leaving the impression that the Egyptian leaders are divided and uncertain what step to take next.

Mubarak had previously pledged to quit office after presidential elections due to be held in September.