Kikwete succeeds outgoing President Benjamin Mkapa, who was constitutionally barred from seeking a third term in polls which the CCM cemented its four-decade hold on power in the east African nation.

“By the virtue of the constitution ... I officially declare Jakaya Kikwete as the elected president of the United Republic of Tanzania,” National Electoral Commission (NEC) chairman Lewis Makame told a news conference.

He added that Kikwete’s running-mate, Ali Mohammed Sheni, would retain his current position as vice president.

According to official results released on Sunday, Kikwete won the election with 80% of the votes, demolishing nine other candidates in Tanzania’s third election since political pluralism was introduced in 1992.

Opposition leader Ibrahim Lipumba, who finished a distant second to Kikwete, accused CCM of rigging the elections, saying its overwhelming victory could only be explained by fraud.

He said his party, the Civic United Front (CUF) would be investigating their suspicions of fraud and would later release a report on its findings.

The CCM, which has ruled Tanzania since independence from Britain in 1961, had been heavily favored to win the elections, partly due to the inability of the fractious opposition to present a unified presidential candidate.

Foreign poll monitors have generally praised the conduct of the elections, which were peaceful in most of the country except on the CUF stronghold of Zanzibar where at least 20 people were wounded in polling day violence

Meanwhile, President Thabo Mbeki congratulated Tanzania on last week’s presidential election, the country’s third since the introduction of political pluralism in 1992.

In a message of support to president-elect Kikwete, Mbeki said: "Once more the sun has shone on efforts of the African people to entrench democracy, stability and good governance with the successful holding of yet another peaceful election in Tanzania."