CAIRO - A US election monitoring group said on Tuesday it was unable to say if Egypt's presidential election was free and fair as it had not been given sufficient access, accusing the military leadership of hampering a transition to democracy.

The Carter Center said it had been unable to monitor the vote properly and that a "return of elements of martial law" meant it was "now unclear whether a truly democratic transition remains under way in Egypt".

Supporters of both presidential candidates - the Muslim Brotherhood's Mohamed Morsy and former air force commander Ahmed Shafik - say their man won last weekend's run-off. Official results are not expected until Thursday.

"We cannot provide a comprehensive assessment of the integrity of the elections due to the limited nature of the mission," the Carter Center's field office director, Sanne van den Bergh, told Reuters.

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