Joao Lourenco has been sworn in as president of Angola, giving the oil-rich African nation its first new leader in 38 years.
Lourenco was inaugurated Tuesday in the capital, Luanda, at a ceremony attended by thousands of Angolans, almost 30 foreign heads of state and outgoing president Jose Eduardo dos Santos.
After Lourenco took the oath of office, dos Santos handed him the presidential necklace, symbolizing the transfer of power.
Dos Santos, who is 75 and rumored to be in ill health, decided not to run for re-election this year, allowing the ruling MPLA party to nominate former foreign minister Lourenco as its presidential candidate.
As promised, main opposition party UNITA and its allies boycotted the inauguration ceremony. The parties unsuccessfully challenged the results of the August general election won by MPLA.
In a 47-minute inauguration speech, Lourenco promised he will fulfill a campaign pledge to reduce corruption, which he said "rages in the institutions of the state."
He also challenged government agencies to show more openness, and "to learn with to live with criticism and difference of opinion and to provoke the debate of ideas."
National interest must be put above private or group interests, he said, adding "it is our responsibility to build a prosperous Angola."
He also pledged to reduce the size of the national government and cede more power to local administrations.
Angola is Africa's second-largest oil producer, behind Nigeria, and takes in billions of dollars per year from oil exports. But most of its 25 million people live in poverty.
"Once I am vested in my position, I will be the president of all Angolans and I will work to improve the living and well-being of all our people," the new president said Tuesday.
Dos Santos was elected president of the party and the country in 1979, after the death of Angola's first president, Agostinho Neto.
Dos Santos and his family are expected to retain a powerful influence in the country's affairs. His daughter Isabel dos Santos is chairwoman of Angola's official petroleum company, Sonangol.