The Presidential Elections Commission (PEC) has extended voting hours on Tuesday to 10pm, as Egyptians cast their ballots in the second day of a two-day election to choose their first leader since last year's ouster of Islamist president Mohamed Morsi.

Voting had ended at 9pm on Monday, but commission head Abdel-Aziz Abdel-Aziz Salman said in a statement on Monday night that Egyptians would have an extra hour to choose either leftist politician Hamdeen Sabahi or former army chief Abdel-Fattah El-Sisi as the country's head of state.

Reports suggested late on Monday that the turnout had been relatively low, with a handful of prominent television anchors urging people to vote en masse on Tuesday.

Egypt's Prime Minister Ibrahim Mahlab also announced late on Monday that Tuesday would be a holiday for employees in the government sector, in order to allow Egyptians to vote.

Mahlab also called on private businesses to grant their employees a holiday so they can cast their ballots.