Ethiopia's new Prime Minister Hailemariam Desalegn took the oath of office, vowing to maintain the legacy of long-time ruler Meles Zenawi who died last month.
"I, Hailemariam Desalegn, in front of the parliament, accept to be the prime minister of Ethiopia," he said on Friday, as lawmakers banged on their desks in support.
Hailemariam, 47, was elected last week as the chairman of the ruling coalition Ethiopian Peoples' Revolutionary Democratic Front (EPRDF), which holds an overwhelming majority in parliament.
"With the decision of the EPRDF and the parliament, I am very happy to take the responsibility of being prime minister," he said after taking the oath.
A close ally of Meles as deputy prime minister and foreign minister since 2010, Hailemariam pledged to continue in the footsteps of Meles who ruled the country for over two decades.
"We brought peace, democracy and development to the country," he said."Meles considered himself as a son of the people," he added, promising to continue "Meles's legacy without any change".
Some analysts have argued that Hailemariam will be handicapped by his relatively young age, limited experience in national politics and the fact he was not part of the still powerful core of ex-rebels who seized power in 1991.
Facing tough challenges in the wider volatile Horn of Africa region, with Ethiopian troops battling Islamist insurgents in Somalia as well as frosty relations with arch-foe Eritrea, Hailemariam also promised to ensure the "security of our country".
Meles, who died at 57, was hailed as an African hero and was a key Western ally in a region home to al-Qaeda-linked groups, but was also criticised by rights groups for a crackdown on basic freedoms.
But in his acceptance speech Hailemariam appeared to address concerns by human rights groups, who have said the new leadership offers an opportunity for change.
"We will reinforce democracy and human rights in the country. If there are problems, we will fix it," Hailemariam said. "We will work with human rights organisations, the national elections board and some opposition parties."
Ethnicity and religion
Education minister Demeke Mekonnen, chosen last week as deputy chair of the EPRDF, was elected deputy prime minister taking over the post from Hailemariam.
"I will serve the country and faithfully serve the prime minister," Demeke said as he took the oath.
He cast his support for Hailemariam, praising his "leadership with the late prime minister" and his "significant role in the EPRDF regarding democracy and the development of the country".
Hailemariam, a Protestant, comes from the minority Wolayta people in the Southern Nations, Nationalities and Peoples Region, where he was president for five years.
Demeke is from the Amhara people of Ethiopia's central highlands, who make up around a quarter of the country's 84 million people, and is a Muslim.
"What is very surprising is that you now have in power a Protestant Wolayta and a Muslim Amhara," a Western diplomat told AFP news agency, noting that for the first time neither of the top two leaders were members of Ethiopia's Orthodox church.
Some analysts say Hailemariam's ethnic origins in the south of the country will play against him as many key figures, like Meles, hail from the Tigray region in the north of the country. Others argue, on the contrary, that his position outside the Tigray power base will work in his favour.
"His ethnicity is considered an advantage, because it is a minority in a multi-ethnic region and, most importantly, not from the numerically dominant Oromo or Amhara," International Crisis Group said in a recent report.