East Timorese voters have gone to the polls to elect a new president in a run-off vote, as the country prepares to celebrate its first decade of independence.

Voters queued to cast their ballots on Monday in a poll that sees Francisco Guterres, popularly known as "Lu Olo", take on Taur Matan Ruak, both heroes of the 24-year war against Indonesia for independence.

The winner of the contest will replace Nobel peace laureate Jose Ramos-Horta, who trailed in third place in the first round of voting, held on March 17. More than 620,000 people in the county of 1.1 million are eligible to vote.

While the role of the president is largely ceremonial, the post has enjoyed a high-profile under Ramos-Horta, and the elections come shortly before celebrations in May to mark 10 years since East Timor gained independence from Indonesia.

East Timorese voters will go back to the polls in July in general elections to choose a new parliament.