Tens of thousands of people cheered as William Ruto was sworn in as Kenya’s president at a ceremony in the capital Nairobi following his narrow election win last month.
Mr Ruto hailed it as “a moment like no other”, adding that a “village boy” had become president.
Defeated candidate Raila Odinga did not attend. He said he had “serious concerns” about his opponent’s victory.
Mr Ruto won the election with 50.5 per cent of the vote, to Mr Odinga’s 48.8 per cent.
Mr Odinga has alleged that the result was rigged, but the Supreme Court has ruled the election was free and fair.
Mr Ruto – the former deputy president – was handed a copy of Kenya’s Constitution and a sword to represent the transfer of power from President Uhuru Kenyatta. With his hand on a Bible, the 55-year-old swore to preserve and protect the Constitution.
“Standing here today is testimony that there is God in heaven. I want to thank God because a village boy has become the president of Kenya,” Mr Ruto said, referring to the fact that he grew up in rural Kenya.
He also had conciliatory words for Mr Odinga, and all his opponents.
“Their supporters will be my constituents. I will work with all Kenyans irrespective of who they voted for,” Mr Ruto said.
New Deputy President Rigathi Gachagua also took the oath of office.
He said the Ruto administration marked “freedom” for Kenya, and the days when people were targeted because of their association with him “are over.”
Earlier, at least eight people were reported to have been injured in a crush as they jostled to enter the stadium to witness the ceremony.
But inside the crowd was in high-sprits, with frequent cheering, waving of the Kenyan flag, and groups of people proudly wearing yellow – the colour synonymous with Mr Ruto’s campaign.
There was also a handshake between the outgoing Mr Kenyatta and Mr Ruto, his former deputy with whom he fell out during their second term in office.
About 20 heads of state from across Africa attended the event.