Egyptian expatriates in 166 countries are heading to the polls for elections to replace ousted leader Hosni Mubarak that are hoped to be the first genuinely contested presidential vote in the country's history.

Elections authorities say less than a million Egyptians out of nearly 10 million living abroad registered to vote.

Saudi Arabia has the largest number of Egyptian voters.

Expatriate voting starts Friday and ends May 17. Voters inside Egypt will cast their ballots on May 23-24. If no candidate wins 50 percent of the votes, a runoff is scheduled for June.