DILI  - Polls opened in East Timor on Saturday, as Asia's youngest nation held its fifth presidential elections since independence, with concerns over political stability and economic security at the forefront.

The 16 presidential hopefuls include former resistance fighter and incumbent President Francisco "Lu Olo" Guterres as well as independence figure and Nobel laureate Jose Ramos-Horta and a former Catholic priest.

At polling booths in the capital Dili, Timorese donned masks and queued patiently as they waited to vote.

"We must choose a new generation so that we can build this country," said one voter, Jorge Mendonca Soares, 42, of his desire for change.

While the nation's independence figures still dominate the field, for the first time there are also four female candidates, including deputy prime minister Armanda Berta Dos Santos.

A recent poll by the national university showed that Ramos-Horta, 72, former defence forces commander Lere Anan Timur and Guterres are the favourites.

Polls close at 3 p.m. with early indicators of who is leading the vote expected to come late Saturday.

If no candidate wins an outright majority, the vote will proceed to a run-off on April 19 between the top two contenders.

Approaching twenty years since independence after the end of a brutal occupation by Indonesia, East Timor has for long spells struggled with political instability.

After the last elections in 2018, Guterres refused to swear in some ministers from the National Congress of the Reconstruction of East Timor (CNRT), a political party led by former prime minister Xanana Gusmao.

The move led to an ongoing political stalemate.

Ramos-Horta, who is backed by Xanana's CNRT party, said earlier this week he was running because he felt the current president had "exceeded his powers".

In East Timor's political system, the president appoints a government and has the power to veto ministers or dissolve parliament.

During a recent election debate, Guterres pledged to ensure peace and stability, defend East Timor's sovereignty and follow the constitution if he won a new term.

Heavily dependent on dwindling supplies of oil and gas, economic diversification and the role of young voters have also been key election issues, with an estimated 20% of voters reaching the voting age of 17 and casting their ballot for the first time.

First-time voter Marco de Jesus, 17, said he felt nervous but relaxed after help from polling staff.

"I feel proud to have carried out my function as a voter," he said, speaing outside a polling station on Dili's waterfront.

"I hope my choice can bring positive and useful change."

(Reporting by Kate Lamb in Sydney; Additional reporting by Nelson Da Cruz and Francisco Ismenio in Dili; Editing by Ed Davies and Raju Gopalakrishnan)