William Ruto has been sworn in as Kenya's fifth president, taking over from Uhuru Kenyatta.
He was sworn in as the crowd at Kasarani Stadium cheered and ululated on Tuesday.
Uganda's President Yoweri Museveni joined other regional and world leaders to witness the ceremony.
As President Ruto carried the bible, the crowd from all corners of the stadium cheered.
Wearing a dark grey suit and yellow tie, Ruto while clutching a Bible as he took the oath of office pledged to "protect and uphold, the sovereignty, integrity and dignity of the people of Kenya".
"I, William Samoei Ruto .... do swear that I will be faithful and bear true allegiance to the Republic of Kenya; that I will obey, preserve, protect and defend this Constitution of Kenya, as by law established, and all other laws of the Republic; and that I will protect and uphold the sovereignty, integrity and dignity of the people of Kenya," he said.
He also pledged to "Do justice to all in accordance with this Constitution, as by law established, and the laws of Kenya, without fear, favour, affection or ill-will".
The oath was administered by Anne Amadi, the Chief Registrar of the Judiciary of the Republic of Kenya.