Abdul Hamid, the speaker of Bangladesh's parliament, has been elected unopposed as president, officials have said, a potentially crucial role as the restive country heads for elections expected next year.

Hamid is a 69-year-old stalwart of the ruling Awami League party who has been serving as acting president after the death of his predecessor Zillur Rahman on March 20.

"Abdul Hamid has won the election uncontested. The chief election commissioner declared him as the winner today [Monday]," said SM Asaduzzman, a director of the election commission.

The post of president, which is elected by parliament, fell vacant last month after Rahman died in a hospital in Singapore following a long illness at the age of 84.

Although the president's role has been largely ceremonial since 1991, when the country switched to a parliamentary system of government, the leader has immense power during the transition of government.

Known for his friendly ties with the opposition parties, Hamid could be thrust into the role of a mediator as the country's two major parties are on a collision course ahead of the next elections due by January 2014.

The main opposition Bangladesh Nationalist Party and its smaller Islamist allies have threatened to boycott polls if they are not held under a neutral caretaker government.

The government of prime minister Sheikh Hasina has rejected the opposition demand, saying the polls will be held under the incumbent government.