US President Barack Obama has declared that “Africa is on the move”, praising the spirit of entrepreneurship at a business summit in Kenya as he kicked off a landmark visit.

Obama arrived in Kenya late on Friday, making his first visit to the country of his father’s birth since he was elected president.

“I wanted to be here, because Africa is on the move, Africa is one of the fastest growing regions in the world,” Obama said.

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“People are being lifted out of poverty, incomes are up, the middle class is growing and young people like you are harnessing technology to change the way Africa is doing business,” Obama told the entrepreneurship summit on Saturday in his first official engagement in Nairobi.

The US embassy itself warned the summit could be “a target for terrorists”, but Kenyan President Uhuru Kenyatta, sharing the stage with Obama, said the event showed a different side to Africa.

“The narrative of African despair is false, and indeed was never true,” Kenyatta said. “Let them know that Africa is open and ready for business.”

A massive security operation was under way in Nairobi, with parts of the usually traffic-clogged capital locked down and airspace also closed for the president’s landing on Friday and his scheduled departure late Sunday for neighbouring Ethiopia.

Top of the list of security concerns is Somalia’s al-Qaeda-affiliate, al-Shabab, who have staged a string of suicide attacks, massacres and bombings on Kenyan soil. Two years ago a Shabab assault on the Westgate shopping mall in the heart of the capital left 67 dead.

Obama said he was delighted to be back.

“It is wonderful to be back in Kenya,” Obama said, also drawing cheers and applause by greeting the summit with a few words of Swahili.

“I’m proud to be the first US president to visit Kenya, and obviously this is personal for me. My father came from these parts.”

Barack Obama Sr was a pipe-smoking economist who the US leader has admitted he “never truly” knew. He walked out when Obama was just two and died in a car crash in Nairobi in 1982, aged 46.

Excitement has been building in Kenya for weeks, with the visit seen 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 al-Shabab 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, and at least 10,000 police officers have also been deployed to the capital.

Kenyatta greeted Obama as he stepped off Air Force One late Friday. The president’s half-sister Auma was also on the tarmac to welcome him and travel in the bomb-proof presidential limousine, nicknamed “The Beast”, for the drive to the hotel in the city centre, where Obama dined with members of his extended Kenyan family.

Counter-terrorism will be a key topic for discussion in bilateral talks with Kenyatta on Saturday afternoon.