Egyptian presidential hopefuls Amr Moussa and Abdel Moneim Abol Fotouh trade barbs about their past in an election debate.

One is a veteran diplomat who once served as Mubarak's foreign minister.

The other an Islamist who was jailed by his administration.

Now Abol Fotouh and Moussa are front runners in the race to replace the deposed president.

In the debate, Fotouh questions Moussa's credibility because he was a minister in the old regime.

(SOUNDBITE) (Arabic) PRESIDENTIAL CANDIDATE, ABDEL MONEIM ABOUL FOTOUH, SAYING

"There is a rule that says the one who created the problem cannot solve it. We revolted against this regime."

(SOUNDBITE) (Arabic) PRESIDENTIAL CANDIDATE AMR MOUSSA, SAYING

"I can also say that you too were silent. You used to defend the positions of the Muslim Brotherhood, not on Egyptian interests but the position of the institution itself. So, the opposition concerned you, not Egypt nor the situation in Egypt. I opposed the situation in Egypt and I was a foreign minister serving Egyptian interests and therefore there was full support from the people to the position of the foreign minister.''

Such a debate would have been unthinkable under the old regime deposed in a mass uprising 15 months ago.

Viewers across Egypt tuned in to watch the contenders battle it out ahead of the historic elections in May.

The debate is the first of a series of face offs between the presidential candidates.

Sarah Sheffer, Reuters