An Egyptian winter

The grounds for the rejection are procedural, including that Mr Abu Ismail failed to meet citizenship requirements as his mother was once an American citizen.

Mr Suleiman was disqualified reportedly for failing to meet the requirement of more than 30,000 verifiable signatures from across various regions of Egypt.

Most controversially, the Muslim Brotherhood candidate al-Shater was disqualified due to a past conviction for criminal offences, although many people regarded the charges as politically motivated and fabricated by the Mubarak regime.

The decision to ban al-Shater seems certain to inflame public opinion if the voting in parliamentary elections held late last year is any guide.

In those elections, the Freedom and Justice Party (Muslim Brotherhood) attracted just less than 37% of the vote while the Nour Party that represents more hardline Islamists received almost 25% of the vote.

If these parties were to form a coalition, it would give the Islamist parties a clear majority in the new Egyptian parliament.

The Muslim Brotherhood has been described as an enormously patient organisation.

It is reportedly proposing that Mr Mohammed Morsi be an alternative candidate who is eligible to run.

The decision to disqualify the leading candidates has created a significant degree of uncertainty, setting the scene for a volatile election campaign and vote.

Also adding to tensions within the country is the trial of those accused of involvement in a Port Said soccer match riot in February that resulted in the deaths of 75 people.

There are nine senior police office among the 73 people charged in relation to the deaths.

The trial has been suspended until early May and a verdict is expected as early as June.