US President Barack Obama arrived in the Kenyan capital Nairobi late Friday, making his first visit to the country of his father's birth since his election as president.

Obama was greeted by Kenyan President Uhuru Kenyatta with a handshake and embrace as he stepped off Air Force One, at the start of a weekend visit during which he will address an entrepreneurship summit and hold talks on trade and investment, counter-terrorism, democracy and human rights.

 The president's half-sister Auma was also on the tarmac to greet him and travel in the bespoke, bomb-proof presidential limousine, nicknamed 'The Beast', for the drive to the hotel in the city centre. Throngs of Kenyans lined the route of the convoy, cheering, whistling and waving as Obama's motorcade passed by and a helicopter circled overhead. A massive security operation was under way in Nairobi, with parts of the capital locked down and airspace also closed for the president's landing and his scheduled departure late Sunday for neighbouring Ethiopia.

Top of the list of security concerns is Somalia's Al-Qaeda-affiliate, the Shebab, who have staged a string of suicide attacks, massacres and bombings on Kenyan soil, including the siege of the Westgate shopping mall in the heart of the capital nearly two years ago that left 67 dead. See also: Photos: President Barack Obama's touch down at JKIA At least 10,000 police officers, roughly a quarter of the entire national force, have been deployed to the capital.

 Excitement has been building in Kenya for weeks, with the visit painted as a major boost for the east African nation's position as a regional hub -- something that has taken a battering in recent years due to Shebab attacks and political violence that landed Kenyan leaders in the International Criminal Court. The visit is also the first ever to Kenya by a sitting US president. Obama is celebrated as a hero throughout the country, yet many Kenyans have been disappointed it has taken him until almost the end of his second term in office to make the trip.

- Human rights on the agenda - A presidential visit to Kenya had been put on ice while Kenyatta faced charges of crimes against humanity for his role in 2007-2008 post-election violence. The ICC has since dropped the case, citing a lack of evidence and accusing Kenya of bribing or intimidating witnesses.

AFP