He said the airline would fund the construction of a safe passage to let about 2,000 elephants follow their natural path north of the snow-capped mountain.

"The African elephant has roamed across the continent from South Africa to the Mediterranean coast but its population is under serious threat," Branson told reporters gathered in a tent by the runway at Nairobi's Jomo Kenyatta International Airport.

"We can create a vital lifeline for the entire animal and human population in the region."

Kenya once boasted more than 100,000 elephants, but that number has plummeted by more than two-thirds in recent years, activists say. Human encroachment is blamed for most of that.

After stepping onto his plane's wing to dance with models and young men in traditional Kenyan warrior dress, Branson defended the environmental impact of his airline.

"It is about striking a balance between the need to combat poverty and the dangers of carbon emissions," he said. Virgin planes would boost the local economy by carrying fresh produce like fruit, vegetables and cut flowers to Western markets.

"There is global warming but there is also extreme poverty."

Virgin will fly daily between London's Heathrow and Nairobi, and expects to carry about 100,000 passengers in its first year.

If operations are successful, Branson has said he hopes to launch a second daily flight. Kenya Airways and British Airways also fly the route.